Since the Convention on Biological Diversity came into force in 1993, access and benefit-sharing (ABS) agreements have been used to facilitate the implementation of bioprospecting projects. While many of these agreements have been negotiated and signed among private and government parties in countries that lack national ABS policies, there are also cases where they have been established under these policies and with the involvement of government agencies that usually enforce a lengthy and slow application process. Empirical evidence shows that national ABS policies have thwarted or delayed access to genetic resources in a few countries (see Brush and Carrizosa 2004 for some examples). Because of reduced access, many companies increased their reliance on existing collections of organisms2 and the potential of modern biotechnology techniques to develop drugs from scratch. This, in turn, discouraged some pharmaceutical, agricultural, and biotech organizations from collecting genetic resources in biodiversity-rich countries. This situation was particularly evident during the 1990s (ten Kate and Laird 1999).
Over the last seven years, several commentators have underscored the fact that despite its decade-long commercial development, combinatorial chemistry3 has failed to put in the market novel drug candidates for the treatment of common diseases, including cancer. Consequently, companies are looking for unexplored groups of organisms such as extremophiles, endophytes, marine organisms, and microorganisms as sources for novel genes and molecular structures. The interest of the industry for these species has also been encouraged by streamlined ABS policies from countries such as Costa Rica, Australia, Samoa, and Thailand (Carrizosa 2004), the increasing possibility to negotiate ABS agreements in countries that lack national ABS policies (Brush and Carrizosa 2004), and recent research that continues to demonstrate the importance of natural products4 for the pharmaceutical industry5 (Newman et al. 2003). These are clear indicators of a renaissance in interest by pharmaceutical and biotech companies in an old-fashioned bioprospecting approach in regions where ABS regulations are permissible and clear. This renaissance is strengthened by scientific advances in the identification of molecular targets for diseases, modern screening techniques, gene technology, large scale culturing of microorganisms, chemical purification techniques, and structure elucidation of natural compounds.
Some pharmaceutical and biotech companies (e.g., those involved in the International Cooperative Biodiversity Group Program) that are going back to the bio-prospecting field are aware of potential benefit-sharing obligations and are prepared to share monetary and nonmonetary benefits derived from bioprospecting ventures. Most of these companies may not be willing to sign ABS agreements that include significant up-front payments such as the famous Costa Rican National Institute of Biodiversity (INBio)-Merck agreement. But they are certainly disposed to provide a share of the royalties, milestone payments, and short-term compensation packages that include training and transfer of technology. They are also looking for counterparts that have realistic expectations for benefit sharing and can add value to the resources collected. This paradigm is reflected in the ABS agreements signed by INBio (see Costa Rican Chapter No. 5, this volume) and in the 2005 Novartis- The National Center for Genetic Engineering and Biotechnology (BIOTEC) three-year agreement aimed at developing new drugs based on genetic resources found in Thailand. In June 2006, Novartis, encouraged by early positive results, renewed the agreement with BIOTEC until May 2001 (BIOTEC Press Release, July 16 2008).6 Another example of this trend was the 2002 collaborative research and benefit-sharing agreement signed between the Japanese pharmaceutical company Nimura Genetic Solutions (NGS) and the Forest Research Institute Malaysia (FRIM) for the collection of soil microorganisms. In late 2002, this relationship was strengthened through the establishment of a subsidiary of NGS under the auspices of FRIM (GRAIN, 2002).7 Similarly, in the last eight years, AztraZeneca has invested about A$100 million in the development of a Natural Products Discover Unit in collaboration with Griffith University8 in Australia. Substances discovered by this joint venture were the source of several patent applications in 2003. Furthermore, in March 2008, Griffith University reported that its partnership with AztraZeneca continues and scientists are currently targeting the development of two promising lead compounds identified from the high-throughput screening of an extensive collection of 45,000 plants and marine invertebrates and their extracts.9
Today, the number of small- and medium-sized biotech and pharmaceutical companies whose core business is the discovery of novel pharmaceutical lead compounds is also increasing and most of them are providing some of the big pharmaceutical and biotech companies with extracts of natural products. For example, the Australian-based company Cerylid Biosciences Ltd has a very extensive library that contains 750,000 extracts. About 80 to 90% of these samples have been collected in Australia and the rest comes from countries such as Malaysia (Sarawak) and Papua New Guinea. Cerylid is also an example of the many firms that have obtained biological samples through collectors such as the Royal Botanic Gardens and the Australian Institute of Marine Sciences. These and other collectors usually establish benefit-sharing agreements with the provider or owner of the resource and a local government agency that include short-term payments and the promise of royalties if products are developed and commercialized. These are examples of ‘best practices’. Nevertheless, it is also important to keep in mind that there are also companies that take the opposite approach with activities that fall within the realm of biopiracy.
While some organizations have recently experienced a renaissance in their interest for genetic resources, others' interest has not flagged. Some have been committed to both the potential offered by these resources, and the ideals of benefit sharing with providers of these resources, for many years. Research organizations such as the United States National Cancer Institute (NCI), aware of the potential of natural products as source of treatments for cancer, have continuously and consistently commissioned botanical gardens and universities to collect biological samples of plants and terrestrial and marine microorganisms, from over 35 countries for the last 40 years (see NCI Chapter No. 6, this volume). About four years before the CBD was drafted the NCI pioneered the use of Letters of Collection (LOC) that proposed benefit-sharing terms in the event of the licensing and development of a promising drug candidate. So far 14 countries10 have signed LOCs. Nevertheless, the NCI is committed to the terms of the LOC irrespective of whether or not an official agreement has been signed (pers. comm. G. Cragg, 18 April 2005). Biological samples collected by the NCI are stored in its Natural Products Repository in Frederick, MD (USA). Pharmaceutical companies such as Aphios Corporation have signed Material Transfer Agreements with the NCI (in 2004) in order to access its natural products repository and they are required by the NCI to comply with the terms of LOCs if products are developed and marketed from the samples covered by these agreements.
The NCI efforts and the CBD mandate have inspired a major international bioprospecting effort called the International Cooperative Biodiversity Groups (ICBGs). Since 1993, the ICBGs have facilitated the participation of 14 major biotech and pharmaceutical companies11 in bioprospecting projects carried out, currently being implemented, or in planning stages in over 20 countries.12 These projects have delivered mixed results and accomplishments (Rosenthal 1999, Brush and Carrizosa 2004, Larson-Guerra et al. 2004, http://www.fic.nih.gov/programs/icbg.html). The Panamanian ICBG (see Chapter No. 7, this volume) describes the scientific implications of the contract negotiation of the ICBG in Panama, one of the most successful ever implemented.
Terrestrial organisms, particularly plants and microorganisms, have been the basis of early developed biotechnology products and continue to be the source of new products, albeit with declining rates of success. Terrestrial microorganisms, for example, have yielded over 120 of today's most important medicines, however, intensive studies of soil microorganisms repeatedly yield species which produce previously described compounds (Jensen and Fenical 2000). Consequently, many scientists have turned their attention to the potential offered by marine organisms and microorganisms, including the so-called extremophiles that are found in extreme habitats where most organisms are not able to survive. Furthermore, in the last few years, scientists have accumulated enough evidence to demonstrate that terrestrial and marine organisms that were thought to be the source of active compounds are just the hosts of microorganisms that are the true producers of these compounds (see NCI Chapter No. 6, this volume). This finding has interesting implications for the sustainable supply of compounds needed for clinical trials and the development of end products.
This chapter first provides an overview of the potential offered by marine organisms, extremophiles, and symbionts that are renewing the interest of bioprospecting efforts worldwide. Increasing scientific evidence reveals the role of symbionts as the real producers of natural products. This and other findings will have key implications for the development of ABS agreements. Following this review the impact of science and modern technologies on the discovery process of natural products is examined. Finally, the chapter concludes with an overview and analysis of selected scientific issues that are likely to influence the negotiation of ABS agreements in the future.
Global estimates of marine diversity vary between 500,000 and 10 million species and with regards to drug discovery this diversity is just beginning to be examined. The oceans started to attract interest from the pharmaceutical industry only since the 1950s with the discovery of two sponge-derived nucleosides that years later served as a lead structure for the development of commercially important anti-viral drugs such as ara-A and the antileukemia drug ara-C (Proksch et al. 2002 and 2003). But the high rate of discovery of interesting compounds and potential products generated in the last two decades has been the result of complex technological advances in diving technology as well as in molecular biology. Such potential was acknowledged in the mid-nineties through a report from the Biotechnology Research Subcommittee (1995) of the National Science and Technology Council of the United States that underscored the importance of marine organisms as a source of new and improved products for the pharmaceutical, crop protection, and bioremediation industries, among others.
In recent years, thousands of active compounds have been extracted from marine organisms that include bryozoans, nudibranchs, sea hares, sponges, soft corals, and tunicates. In January 2006 Marinlit, a database of marine natural products literature, reported that about 15,100 compounds had been derived from 3,088 marine species. Three years later, the number of compounds registered by the database has increased to 22,000 compounds derived from 3,355 species (http://www.chem.canterbury.ac.nz/marinlit/marinlit.shtml). In spite of such increasing amazing diversity of compounds only a few approved pharmaceuticals derived from marine organisms (e.g., cytarabine and vidarabine) have reached the market (Kijjoa and Sawangwong 2004). Nevertheless, as Faulkner (2000) argues ‘pharmacological research involving marine organisms is intrinsically slower and has disadvantages compared with a program based on synthesis, but the number and quality of the leads generated more than justify research on marine pharmacology.’ A handful of such lead compounds have contributed to the development of over 15 marine products derived mostly from invertebrates (sponges, tunicates, mollusks, and bryozoans)13 that are currently in clinical trials mostly in the areas of cancer, pain, and inflammatory disease (see Table 1, this chapter). In addition, since the identification of new compounds is progressing as suggested by the Marinlit database, the potential for new drugs is not only promising, but it is becoming a reality. Revolutionizing compounds like ziconotide (also known as Prialt®), isolated from the cone Conus magus, came out of the pipeline of clinical trials a couple of years ago. The European Union and the USA Food and Drug Administration approved ziconotide for the treatment of severe chronic pain in February 2005 and January 2004 respectively. This is the first compound in over 40 years that has been added to the repertoire of drugs for treating severe pain. Ziconotide is a thousand times more potent than morphine and it works by preventing neurotransmitter release at the synapse, thus blocking pain sensation (Garber 2005). On the other hand, most compounds do not get to market. For example, didemnin B, isolated from a tunicate found in the western Caribbean Sea, went through Phase II clinical trials but it was abandoned during human trials due to its high toxicity. Similarly, girolline and jaspamide, isolated from the Melanesian sponge Pseudoaxyssa cantharella and the Indo-Pacific sponge Jaspis splendus, respectively, were also withdrawn from clinical trials due to their extremely toxic side effects (Arif et al. 2004).
The wealth of bioactive metabolites isolated from marine invertebrates that usually lack morphological defenses is a clear indicator of the importance of these compounds for the survival of the species. It has been demonstrated that chemical defense is an effective strategy to fight off predators or to ward off other species competing for space or food (Proksch and Ebel 1998). Therefore, most drug candidates from the sea have been isolated from sessile invertebrates that inhabit coral reefs in tropical or subtropical waters where there is great competition for space and food and significant pressure from predators such as fishes. Deep-diving technologies and remote-operated machines have also opened the possibility to collect and examine the pharmacological potential of entremophiles or organisms that live in extreme environments, such as the deep-water sponge Discodermia dissoluta. This sponge is the source of discodermolide, a secondary metabolite, that has shown potent anti-tumor activity against human lung cancer cells and breast cancer cells and it is currently in clinical trials (see Table 1, this chapter) (Proksch and Ebel 1998). Scientists have found that cytotoxicity of marine organisms clearly surpasses those of terrestrial origin. Therefore, it is no surprise that marine natural products have found their stronghold in the area of anti-cancer chemotherapy (see Table 1, this chapter). Kosan Biosciences, Pharma-Mar, and Eisai Medical Research Inc., for example, have in preclinical and clinical trials several anti-cancer drug candidates from marine genetic resources (http://www.clinicaltrials.gov/ct/show/NCT00100932, http://www.pharmamar.com/es/pipeline/).
Marine organisms also have great potential as a source of compounds for other industries that include cosmetics, agribusiness, and orthopedics. Chitin and chitosan have been used in several areas of technology for many decades. Chitin, a polysaccharide, is abundantly available from the shells of arthropods such as shrimp and crab. Chitosan is a biopolymer derived from chitin. These two compounds have multiple applications in drug delivery, cosmetic formulation, surgical wound dressing, hypertension, textiles, and dietary supplements. The skeleton of individuals of the coral family Isididae has also being used as an orthopedic implant in bone grafting surgeries (Maxwell 2005). The pseudopterosins are a group of anti-inflammatory and analgesic compounds isolated from the Caribbean sea whip (Pseudopterogorgia elizabethae) that have cosmetic applications. The company Estée Lauder brought one of the pseudopterosins to market in record time as an additive in the cosmetic line Resilience. It should be noted that economic benefits have not been shared with the Bahamas which is the source country of samples of the Caribbean sea whip (NBSAP 1999, pers. comm. R. Newbold, 28 October 2005).
Many eukaryotes14 are themselves involved in a variety of intimate associations with other organisms ranging from symbiotic to pathogenic. In the last decade, scientists have accumulated significant evidence suggesting that bacterial symbionts are responsible for the production of a wide range of natural products isolated from eukaryotes such as plants (Piel 2004). There are many highly evolved groups of microorganisms, known as endophytic microorganisms, residing in the living tissues of plants. Endophytic microorganisms such as fungi and bacteria are found in every plant on earth (over 300,000 species of higher plants) and they produce a great variety of substances that ensure the protection and survival of the host plant. Only grass species (i.e., Neotyphodium sp.) have been extensively studied relative to their endophytic biology (Piel 2004). Isolation and culturing of individual endophytes have led to the identification of a great variety of substances that include antibiotics, antimycotics, antidiabetic, antioxidant, insecticidal, immunosuppressants, and anticancer compounds. Some of the most interesting compounds produced by endophytic microbes include cryptocin, cryptocandin A, jesterone, oocydin, isopest, acin, the pseudomycins, and ambuic acid (Strobel et al. 2004).
In addition, some plants that generate bioactive natural compounds have associated endophytes that generate the same product. This is the case of the fungus Taxomycetes andreanae that was isolated in 1993 from the yew tree Taxus brevifolia. Both the fungus and tree produce the famous anticancer agent taxol (Suffness 1995). This might be related to a genetic recombination of the endophyte with the host that occurred during the course of the evolution of these organisms. Therefore, if endophytes can produce the same compound as the host plant this has important implications that might facilitate the sustainable supply of this compound at industrial levels. It is recognized that a microbial source of a high value product may be easier and more economical to produce thereby reducing its market price. However, a great deal of uncertainty exists between what an endophyte can produce under in vitro conditions and what it may produce in nature. All aspects of the biology and relationship between endophytes and their hosts are a vastly unknown and under-investigated field (Strobel et al. 2004).
In the marine realm, invertebrates such as the sponge Dysidea herbacea contain bioactive compounds of great pharmaceutical interest that can also be found in associated organisms. The sponge tissue is loaded with Oscillatoria spongeliae, a cyanobacterial symbiont which comprises about 50% of the cellular volume of the sponge. Further analysis has shown that the same bioactive compound can be isolated from the symbionts (Bewley and Faulkner 1998). Circumstantial evidence for a microbial origin of natural products isolated from marine microorganisms also exists for many marine invertebrates. For example, the active compound isolated from the mollusk Dolabella auricularia is also found in the blue-green alga Symploca hydnoides (Harrigan et al. 1998). Clearly, isolation and cultivation of microbial producers of active compounds provide an alternative to facilitate the sustainable supply of these organisms. This can be a viable and cost-effective approach provided that appropriate microbe culture techniques are available. However, this does not seem to be the case for some marine symbionts.
In the last decade scientists have been particularly interested in a largely unexplored group of microorganisms that thrive in extreme environments. Some estimate that there are about 2 million species of bacteria in the sea and close to 4 million species of these organisms in a ton of soil (Curtis et al. 2002). Similarly there are about 1.5 million species of fungus in an average soil sample and only 100,000 have been described (Hawksworth 2004).
Diversa Corporation, Genencor International, Novozymes, and Vicuron Pharmaceuticals are just a handful of companies that have taken advantage of this diversity. They collect samples of bacteria and fungi that have multiple applications in the pharmaceutical, biotech, agribusiness, chemical, cleaning, and food industries. These companies also have great interest in the so-called extremophiles (or extreme-loving organisms), which include bacteria, archaea,15 protists,16 and eukaryotes that live under extreme conditions that would usually kill other creatures. Scientists have identified several categories of extremophiles that include the following:
Acidophiles or acid-loving organisms live in habitats that present pH values less than 2 (e.g., the archaea Ferroplasma acidiphilum can catalyze the accelerated dissolution of sulfidic minerals in industrial tank bio-leaching operations) (Okibe et al. 2003).
Alkalophiles or alkaliphiles thrive in acidic conditions at pH values higher than 10. (e.g., a species of Streptomycetes collected from the soda mud flats on the shores of the alkaline Lake Nakuru in Kenya is the source of a cellulase isolated by a Dutch academic researcher, and later commercialized by Genencor International to create the popular stonewashed look in denim jeans (http://www.genencor.com/wt/print/biodiversity).
Barophiles or piezophiles are organisms that need high pressures to grow. Recovered at great ocean depths, some of these organisms require pressures hundreds of times greater than that on Earth's surface to survive (e.g., Photobacterium profundum is found where pressures reach 25 megapascals and it is an excellent model for studying adaptation to cold temperatures and high pressures) (Vezzi et al. 2005).
Anaerobes are organisms that do not require oxygen to carry out respiration. Some strict anaerobes are actually inhibited from growing in the presence of oxygen (e.g., bacterium Bacillus infernos or ‘bacillus from hell’ is not only anaerobic but also thermophilic. It was obtained at a depth of approximately 2,700 m below the land surface) (Boone et al. 1995).
Halophiles or salt-loving organisms inhabit environments consisting of 20 to 30% salt (e.g., the bacterium Halobacterium halobium has a protein known as bacteriorhodopsin which is light sensitive and is used in optical switches) (Roy et al. 2002).
Psychrophiles or cold-loving organisms (e.g., bacterium Polamorolas vacuolata, found in Antarctica grows best at 4°C and cannot survive at temperatures above 12°C). Some of these organisms have enzymes that work at refrigerator temperatures and might have applications in the food industry. They also help clean up artic oil spills (Madigan and Marrs 1997).
Thermophiles and hyperthermophiles are heat-loving organisms that grow at temperatures between 50 and 70°C (e.g., the frequently cited bacterium Thermus aquaticus found in the 1960s in a hot spring in Yellowstone National Park (US) and source of the enzyme Taq polymerase used in the multimillion Polymerase Chain Reaction (PCR) technique used for the replication of DNA) (Brock 1997).
Extremophiles can be found in both terrestrial and marine ecosystems and some of them have also been discovered in the most unusual places and circumstances. In 1956, the bacterium Deinococcus radiodurans was found in cans of meat that had been exposed to supposedly sterilizing doses of radiation. This is the most radiation-resistant organism known to man. It can withstand exposure to radiation levels up to 1.5 million rads (500 rads is lethal to humans). A recombinant strain of this bacterium has been engineered to degrade organopollutants in radioactive, mixed-waste environments (Cavicchioli and Thomas 2000). Genetic engineering techniques used to create this strain of bacterium paved the way for several technologies that have facilitated the discovery of natural products in the last decade. The next section provides an overview of the role of these and other technologies.
In the last 40 years or so, scientists have defined the underpinnings of the scientific process of discovery of natural products (i.e., chemical compounds with pharmaceutical, agrochemical, or other industrial uses) which in most cases is usually initiated with the isolation of crude extracts from biological organisms that are purified through a technique known as pre-fractionation. This technique basically increases the concentration of the chemical compounds. The purified extracts are then tested in biological assays in order to identify chemical compounds that are active against a human or plant disease. Subsequently, the chemical compound can either: a) be isolated, purified and used as a drug or agrochemical; b) require structural modification to increase potency and specificity; or c) be used to develop analogs that are structurally less complex and easy to synthesize in the laboratory (ten Kate and Laird 1999, Rosenthal et al. 1999).
In the last two decades, modern technologies have not only improved the diversity and accuracy of screens but also facilitated and accelerated steps (b) and (c). Furthermore, developments in genomics, bioinformatics, and novel genetic engineering techniques have turned bacteria into factories for the production of large quantities of natural products. This section presents an overview of the linkages between these and other techniques that promote the mutation and evolution of genes and their contribution for the production of natural products in future decades.
In the last few decades, as underscored in the previous section, scientists have standardized the scientific process of discovery of natural products. In 1995, a major contribution to the field occurred with the availability of the complete genomic sequence of the first living bacterium Haemophilus influenzae which opened the field of microbial genomics. Since then, over 100 microbial genomes have been completely sequenced and published and another 200 are estimated to be in progress worldwide. Beyond sequencing, there have been major advances in the field of functional genomics where whole genomes are being characterized in more detail using proteomics and microarray technologies. DNA microarrays, for example, allow for the identification of genes that are turned on or off under different environmental conditions on a genome-wide scale. Also, comparative genome hybridization (CGH) studies that employ DNA microarrays are revealing the extent of diversity across arrays of related and unrelated microbial species (Nelson 2004).
Developments in genomics, proteome analysis, and bioinformatics have also enabled scientists to gain a better understanding of the chemical pathways and reactions in living organisms which have led to the identification of new targets for drugs. The targets are proteins produced by genes that cause the disease. Once the genetic basis of a disease and the proteins involved in its phenotype have been elucidated, these proteins can be used as targets in high-throughput screening (HTS) for drug development. Advances in gene technology have also allowed the speeding up of screening programs for new compounds through the development of more sophisticated in vitro assays. For example, genes encoding receptor proteins for certain classes of drugs or enzymes may serve as targets for novel drugs or pesticides that may be cloned and expressed on a large scale in high-throughput in vitro assays into which thousands of plant extracts may be applied (Schmid 2003).
As well as finding a suitable target, an important part of the challenge of designing an assay is to find a way to detect whether the compound being tested for its potential effect as a drug does or does not produce the desired result on the target. Thus, an assay usually involves some indicator, a chemical which changes color or reveals in some manner whether the potential drug molecule has interacted biologically or chemically with the target, for example, by killing a cell or rendering an enzyme inactive. There are mechanism-based and whole-organism assays. Mechanism-based assays use individual biochemicals such as enzymes or receptors isolated from cells that will reveal specific biological activity when combined with the chemical to be screened. In this case a collection or library of chemicals to be tested is built and maintained. Each of the chemicals will be tested many times against an ever-changing array of mechanism-based assays. Mechanism-based assays are often changed every three months (Kingston et al. 1999).
On the other hand, whole-organism assays operate in vivo and expose an entire cell to the chemical being screened, enabling the potential drug to operate through a range of different mechanisms during the one test. In this approach the assay remains the same. New assays are continually being developed and very few, if any, plants have been screened using all the techniques now available. Also the pattern of disease distribution is not static. As some diseases are brought under control others gain prominence and new ones evolve.
In addition to an increasing understanding of genes, targets, and assays, advances in miniaturization and automation of HTS have accelerated the discovery process of new pharmaceuticals. This means that many more biochemical compounds can be screened more rapidly and effectively. HTS screening can test over 1.1 million compounds in six months (Schmid 2003).
Combinatorial chemistry is part of an increasing set of tools and procedures to expedite the discovery process of pharmaceuticals and agrochemicals. Combinatorial chemistry allows the generation of a huge number of chemical compounds for screening. This is based on the idea that all but the smallest organic molecules can be thought of as made up of modules which can be assembled in many ways. By going through all the possible combinations a huge number of molecules can be created from a small number of starting modules.
Combinatorial chemistry techniques have been used to create large numbers of organic molecules called libraries that can be screened at one time. In the past, chemists have traditionally made one compound at a time. For example, compound A may have been reacted with compound B in order to produce compound AB which may have been isolated and purified through crystallization, distillation, or chromatography. In contrast, combinatorial chemistry offers the potential to make every combination of compound A1 to Ax and compound B1 to Bx. The range of combinatorial techniques is quite diverse and these compounds can be made individually in a parallel or in mixtures, using either solution or solid phase techniques (Schmid 2003).
These techniques have allowed an exponential increase in productivity never seen before. In the last century, scientists may have reported the existence of several million biochemical compounds, but today using combinatorial chemistry techniques it is possible that new discoveries will surpass that total amount in a relatively short period of time. Furthermore, in the 1970s a traditional chemist was able to produce about four compounds in a month at a cost per compound estimated to be about US$7,500. Today, using combinatorial chemistry techniques the same chemist can produce over 3,000 compounds in the same period of time at a cost per compound of about US$12 (Borman 1998). This is possible not only due to a convergence of chemistry and biology but also because of fundamental advances in miniaturization and robotics. This relatively new field has captured the attention of scientists in the pharmaceutical, biotechnology, agrochemical, and other industrial areas.
After almost two decades, however, as the poor record of development of novel products demonstrates, combinatorial chemistry has not led to many successful products. Furthermore, half of the ten best-selling drugs are derived from secondary metabolites originally isolated from microorganisms or plants. Organic chemistry has not caught up with the capacity of nature to create new structures with a complex molecular diversity. Chemists have the building blocks but they need the directions in order to put them together in a manner that provides benefits to society. The natural world offers the manual. Some argue that organisms making natural products have been conducting combinatorial chemistry and have been screening for activity for hundreds of millions of years before humans adopted a similar strategy (Firn and Jones 1998). The deadly South Pacific cone snail, for example, uses a highly effective peptide toxin to paralyze its prey. This toxin is a mixture of 100 or more venoms produced by the combinatorial scrambling of amino acids that has taken place over 30 to 50 million years of evolutionary history of the cone snail. There are more than 500 species of cone snails, each able to produce more than a hundred unique toxins and they are yielding new treatments for pain, epilepsy, and incontinence (see section ‘Marine organisms’, this chapter).
Some argue that the number of possible new drug and agrochemical targets (e.g., proteins produced by genes that cause the disease) has already outgrown the number of existing compounds that could potentially serve as drug candidates. Nonetheless, classical combinatorial chemistry has its limits when it comes to synthesizing new molecules. Also, rational drug design, although successfully used to develop HIV protease inhibitors, is still in its infancy. Naturally occurring compounds account for about one-third of the products that comprise the US$500 billion industry (ten Kate and Laird 1999). Natural products will stay valuable for pharmaceutical, biotechnology, and agrochemical industries due to their wide structural diversity, their excellent adaptation to biologically active structures, and their genetic diversity. Furthermore, in the last few years, recombinant DNA techniques popularly termed ‘gene cloning’, ‘genetic engineering’, or ‘synthetic biology’ have taken advantage of this genetic diversity and offered unlimited opportunities for creating new combinations of genes and natural products.
Genetic engineering is the formation of combinations of heritable material by the insertion of nucleic acid molecules produced by whatever means outside the cell into any virus, bacterial, and plasmid on another vector so as to allow their incorporation into a host organism in which they do not naturally occur but in which they are capable of continued propagation. In essence, gene technology is the modification of the genetic properties of an organism by the use of recombinant DNA technology. Genes are the biological software that drive the growth of organisms.
Recombinant genes found in wild biodiversity used to be more important for agriculture17 than for the pharmaceutical or biotechnology industries but this is changing. The transfer into plants or microbes of genes from viruses, bacteria, animals, and plants is becoming a standard practice in the pharmaceutical, agrochemical, food, cleaning, and other biotechnology industries. In these industries, recombinant DNA research and development does not require the same amount of random screening carried out in traditional bioprospecting practices. Recombinant pharmaceuticals, agrochemicals, and other biotechnology products are primarily the result of a product-orientated engineering approach (Schmid 2003). In this context, bioprospecting has become a strategy to accumulate and develop libraries of novel genes and proteins from plants, animals, and microbes that are used according to specific needs and circumstances. For example, leeches have been used in traditional medicine to treat thrombosis since ancient times. The active principle from their saliva, the protein hirudin, is now an ingredient of numerous ointments and gels used against varicosis and hemorrhoids. Genetic engineering techniques have facilitated the development of recombinant hirudin that is now being produced by Escherichia coli (Schmid 2003).
Today, the search for plants, animals, and microbes with pharmaceutical, agrochemical, and other industrial purposes offer many opportunities for the discovery of genes coding for enzymes and proteins involved in natural-product biosynthesis, many of which might be expected to have a broad substrate tolerance. The addition of these genes to organisms with existing rich natural product diversity should generate even more chemical diversity producing chemical structures that currently lie beyond the scope of combinatorial chemistry. This is the premise of the so-called relatively new field of synthetic biology which involves taking genes and their metabolic pathways found in nature and grafting them into the genetic code of a microbe. The microbe or host organism reproduces and expresses the added genes through the production of natural products.
The term ‘synthetic’ comes from the fact that the resulting natural product comes out of an organism with a genetic code that is not ordinarily found in nature. For example, the malaria-fighting compound artemisinin is naturally produced by the wormwood (Artemisia annua), a plant indigenous to Africa and Asia, but in very low quantities. Scientists at the University of California, Berkeley are trying to increase the production level of artemisinin in order to reduce its cost for poor consumers by extracting the artemisinin-producing genes from the wormwood plant and inserting them into the common yeast used in breads and beer. In early 2006, after almost three years of work, the scientists proved that the yeast can produce artemisinic acid, a chemical precursor of artemisinin. Now chemists can use a simple and inexpensive purification process to turn artemisinic acid into the drug artemisinin. Although the yeast is capable of producing artemisinic acid at a higher level of productivity than the wormwood plant, industrial scale-up is required to raise artemisinic acid production to a level high enough in order to reduce the cost of artemisinin therapies (Ro et al. 2006). This process is likely to take two to four years (Hoffman 2006).
A few years ago, DuPont scientists pursued a similar synthetic biology experiment by transplanting six genes from two different microorganisms into one microbe. The microbe produced four different enzymes that together turn affordable, corn-derived glucose into propanediol the key ingredient of Sorona, a soft static-resistant polymer DuPont markets as an alternative to polyester and nylon. Before this procedure was designed, instead of the affordable glucose, DuPont scientists were using petroleum for the production of Sorona. This new technology allowed not only a reduction in costs but also in toxic byproducts (Weintraub 2004).
Similar initiatives have been pursued by the enzyme industry. Genencor International, for example, obtained extremophile bacteria that had bee collected by academic researchers (see section ‘Extremophiles’, this chapter) in a highly alkaline lake in East Africa that included genes used to create enzymes for the laundry detergent Tide. The extremophile genes responsible for making these enzymes were genetically engineered into the commonplace bacteria E. coli which was then grown massively in giant brewers' vats. It should be noted that Genencor International has over 15,000 strains of microbes stored in deep-freezers in Palo Alto, CA and the Netherlands. Such potential has delivered 11 products that involve the use of living material, enzymes, and proteins to develop cleaner and cheaper ways of making industrial chemicals.
‘Directed evolution’ is a procedure used in genetic engineering to evolve proteins or RNA with desirable properties not found in nature. Directed evolution is usually guided toward a predetermined goal resulting largely in the accumulation of adaptive mutations, whereas natural evolution accumulates adaptive and neutral mutations. The type of properties targeted in in vitro evolution often goes beyond requirements that would make biological sense.
The directed evolution technique involves the following three steps: 1) Diversification: The gene encoding a protein of interest is mutated or recombined at random in order to develop a large library of gene variants; 2) Selection: the library is tested for the presence of mutants that exhibit the desired properties using an assay or screen and; 3) Amplification: the mutants identified by the assay are replicated in order to allow scientists understand the type of mutations that have occurred. Directed evolution can be carried out in living cells (in vivo) or directly in DNA (in vitro). Unlike in vivo directed evolution, in vitro experiments can generate large DNA libraries. Directed evolution in which as genome sequencing projects continue to grow, promises to become a principal route for search and discovery.
This technique indeed offers a totally new dimension for bioprospecting. The first successful examples of protein or amino acid sequence improvements are the results of screening genes from the wild. Calcitonin is a peptide hormone that inhibits the release of calcium ions and phosphate from the bones and has therapeutic uses for osteoporosis. Research on related hormones from animals revealed that the calcitonin from salmon is more active and has a longer half-life within the human body than the human peptide structure. Protein engineering based on computer simulation and combinatorial chemistry techniques are very powerful tools that can take advantage of the genetic diversity offered by the natural world in order to develop new biotechnology products (Otten and Quax 2005).
Companies such as Genencor International and Diversa Corporation have managed to isolate DNA from environmental samples without culturing and to accelerate the evolution of its genes through a technique known as site-directed mutagenesis. This is a technique in which a mutation is created at a defined site in a DNA molecule.
Site-directed mutagenesis generates diversity by specific random or cyclic mutagenesis approaches. Thus, scientists are able to generate large information-rich libraries of unique molecules. The selection and screening possibilities are knowledge based, high throughput, and product oriented. The libraries generated are screened for the targeted properties and the best candidate is selected. They perform protein engineering augmented by knowledge derived from structures determined by x-ray crystallography, computational homology modeling, rapid protein characterization, and structure/function relationship analysis to create new products. Scientists have determined over 100 structures for different enzymes including proteases, lipases, amylases, and cellulases. If scientists are unable to find an enzyme to solve a specific problem in nature they are able to develop it by imitating evolution (i.e., molecular evolution). They replicate mutation and recombination in lab conditions. By forcing enzymes to evolve, many new enzyme products are discovered.
The company Diversa Corporation, for example, uses a genomic approach in which DNA is isolated directly from environmental samples without culturing. Using Diversa Corporation's gene site-saturation mutagenesis (i.e., a variation of site-directed mutagenesis) and turntable gene reassembly this company has been able to evolve genes in order to create multiple variants based on the original nucleic acid. These genes are then screened for characteristics and activity required for the end product or application. The resulting nucleic acid is then included into Diversa Corporation's proprietary environmental gene libraries which are then screened for a host of various products. Diversa Corporation's unique proprietary approach to discover and evolve novel genes has created environmental libraries comprising millions of genomes. For example, Diversa Corporation marketed a custom enzyme (Luminase) for bleaching paper. The enzyme was collected from organisms collected in a soil sample found near geysers in Russia and then it was engineered to work at different temperatures and alkaline levels (Kretz et al. 2004).
Recent scientific findings such as the role of most symbionts (e.g., algae, bacteria, and fungus) as the true producers of natural products and novel technologies that can turn genetically altered bacteria into factories for the production of natural products suggest that both users and providers of genetic resources need to negotiate ABS agreements that reflect these scientific developments and trends. This section underscores key implications of these and other scientific issues that are relevant for bio-prospecting ventures. These implications are described in the context of the following activities that are usually addressed by most ABS agreements: a) identifying biological samples, b) supplying biological samples, and c) transferring technology and building capacity.
Successful providers of genetic resources have relied on their expertise to identify biological samples as a strategy to add value to samples and to protect their identity. Organizations such as the Costa Rican National Biodiversity Institute (INBio) (see Costa Rican Chapter No 5, this volume) have developed a barcoding technology to tag and track specimens. This is a key component of the INBio inventorying process and information system that is particularly well developed for plants. Since INBio has already identified over 90% of all Costa Rican plants, this provides a comparative advantage in the negotiation of ABS agreements relating to collection of plant species, because there is an implicit assumption that the identity of the plant will be the same as the identity of the source of the natural product. Nevertheless, increasing evidence indicates that in many cases the producers of natural products are not the plants and animals themselves but the fungi, algae, bacteria, and other microbes that live in association with these organisms (see section ‘Symbionts: Are They the True Sources of Natural Products?’, this chapter).
This discovery presents a new technical challenge to all providers of these resources if they want to provide the identity of the sample as an element to add value to the bioprospecting process and the negotiation of ABS agreements. Many of the chemotaxonomy and genomic techniques available to identify algae, fungus, and bacteria are very expensive and are currently available in very few well-equipped laboratories based in developed countries.
Several chemotaxonomy and DNA fingerprinting methods for the classification of microbes are available and relatively useful, but each has specific limitations and are data dependent. For example, bacterial phylogenetic classification is based on a sequence analysis of the small subunit 16S ribosomal RNA molecule or its genes (Priest 2004). A major limitation of this approach is that small ribosomal subunit sequencing is not suited for large numbers of isolates that could be provided by bioprospecting initiatives. Therefore, this method is often combined with high-throughput methods such as Fourier-transform infrared spectroscopy. The Center for Microbial Ecology of Michigan State University promoted this concept by establishing a publicly available database that facilitates the identification of bacteria by providing the scientific community with ribosomal RNA phylogenetic trees and ribosome-related data (http://rdp.cme.msu.edu/).
The identification and classification of bacteria and other prokaryotes (i.e., organisms without a cell nucleus) is markedly data dependent and it is still relatively data poor. Moreover, classification procedures are in a constant state of change with each influx of new technology and new data. Prokaryotic systematics is wrestling with the imbalance between high-throughput sequencing and the concept of polyphasic taxonomy.18 It should be emphasized that currently bacterial taxonomy is reliable only at the level of broad phylogenetic groups (well delineated by even partial 16S sequences) and at the species level with certain well-studied taxa such as the genus Mycobacterium. For many genera, identification of species remains a major problem as exemplified by the genera Nocardia and Rhodococcus (Goodfellow and O'Donnell 1993).
Chemotaxonomy is another approach that has been useful to identify plants, bacteria, and other microorganisms. Chemical data from the analysis of whole organisms and cell components using methods such as gas, thin-layer, and high-performance liquid chromatography, have been used extensively to classify microorganisms according to the discontinuous distribution of specific compounds. Chemotaxonomic analysis of macromolecules, especially aminoacids and peptides, isoprenoid quinines, lipids, polysaccharides and related polymers, proteins, and enzymes were used to classify innumerable taxa prior to the introduction of 16S rDNA sequencing. Chemotaxonomic data proved to be of particular value in the classification of the actinomycetes and coryneform bacteria which initially was essentially morphological in concept. Data from amino acid and sugar analyses promoted an extensive reappraisal of the classification of these taxa (Goodfellow and O'Donnell 1993, Priest 2004).
Chemotaxonomy is also contributing to polyphasic taxonomic characterization and it will continue to be important with the availability of high-throughput chemical fingerprinting methods for characterization and identification such as Fourier-transform infrared spectroscopy, pyrolosis mass spectrometry, matrix-assisted laser desorption-ionization with time of flight and spray-ionization mass spectrometry. These high-throughput chemical fingerprinting methods offer the possibility of integration between genomic and phenotypic characterization of organisms which are important, if one is to understand much of the current data and to exploit technology to solve the major problem of rapid and reliable identification of microbes. In general, good congruence has been found between the discontinuous distribution of chemical markers and the positions of the corresponding taxa in the phylogenetic tree as clearly shown with respect to actinomycetes (Priest 2004).
This technology, despite its limitations, is important, particularly in those bioprospecting projects where taxonomy has to be assessed and this increases the likelihood of getting a good bioprospecting deal. But an organism should be identified only when a promising lead natural product is identified. Negotiating the inclusion of molecular and genomic taxonomy efforts into agreements is an important option for providers of genetic resources. Nevertheless, if synthetic, semi-synthetic or genetically engineered derivatives are the final product then the user will not need to re-supply by acquiring additional samples. In this case, the identification of the original biological sample is relevant only for scientific purposes.
Increasingly, evidence is showing that many of the compounds isolated from marine organisms are produced by symbiont microorganisms. In addition, scientists are focusing on the potential offered by microorganisms including extremophilic bacteria, fungi, and algae. This finding is consistent with INBio reports regarding international requests to collect microorganisms in Costa Rica (see Costa Rican Chapter No. 5, this volume). The advance development of a drug or agrochemical usually requires access to large quantities of the source raw material for production of sufficient drug for preclinical/clinical and product development. As previous sections indicate, new scientific techniques have been developed to grow fungi, algae, bacteria, and other microorganisms in in situ and ex situ conditions. Many of these microbes live in symbiosis or association with other organisms such as plants and marine invertebrates. In most cases, the symbionts can be isolated and cultured in the laboratory in order to obtain large quantities of the active compound. In other cases, both organisms, the host and symbiont, have to be grown together in in situ conditions through mariculture or aquaculture techniques.
Marine sponges, for example, are known to include cyanobacterial symbionts that produce secondary metabolites with pharmaceutical potential. A few years ago, scientists assessed the technical and economical potential of using marine sponges for large-scale production of these compounds for two cases: a) the anticancer molecule halichondrin B from Lissodendoryx sp. and b) avarol from Dysidea avara for its antipsoriasis activity. An economic and technical analysis was done for three potential production methods: a) mariculture, b) ex situ culture (in tanks), and c) cell culture. The conclusions indicated that avarol produced by mariculture or ex situ culture could become a viable alternative to currently used pharmaceuticals for the treatment of psoriasis. Production of halichondrin B from sponge biomass was found not to be a feasible process, mainly due to the extremely low concentration of the compound in the sponge (Sipkema et al. 2005).
On the other hand, some marine chemical products are naturally more amenable to economical production via laboratory synthesis or semi-synthesis. This is usually related to either the overall complexity of the model compound and/or the number and nature of the steps contained in the biosynthetic pathway. For example, the structural simplicity of some compounds such as dolastatin (originally derived from the sea hare Dolabella auricularia, but found to be cyanobacterial in origin (Luesch et al. 2002) make them prime candidates for their total synthesis. In contrast, a natural product such as ecteinascidin 743 (ET-743) with 60 or more steps required for complete synthesis (Luesch et al. 2002), may never be economically produced in its entirety by synthetic chemists. Analogs of this complex compound, however, can be produced through a semi-synthetic strategy that starts with and builds on one or more precursor molecules. For example, efficient semi-synthetic production of ET-743 has been attained by using the closely related compound safracin B as a starting point. This natural product is produced by an easily culturable pseudomonad bacterium, allowing sustainable and cost-effective semisynthetic production of ET-743 (Luesch et al. 2002). Table 1 lists selected current natural products derived from marine organisms that are being cultured in in situ and ex situ conditions and manufactured via laboratory synthesis or semi-synthesis.
Genomic approaches have also been developed to ensure a sustainable supply of natural products. For example, scientists are working on approaches to:
Isolate the organism's genes that can subsequently be used to produce the natural product in another organism (e.g., synthetic biology), For example, the bioprospecting program of the Bermuda Biological Station for Research is developing techniques for cloning genes from the host macrofauna and associated microbial symbionts of sponges and other marine invertebrates and inserting them into laboratory bacterial strains (http://www.sciencemag.org/cgi/content/abstract/sci;1093857v1). The hope is that targeted natural products can be sustainably produced using such a strategy, even if the microbial agents responsible for them remain unable to be cultured or even identified.
Facilitate the identification and expression of gene clusters from microbes (e.g., fungi such as actinomycetes) that do not produce metabolites in natural conditions (Streit and Schmitz 2004).
Evolve genes that can be screened later against a desired property for a specific product (see section ‘Genetic Engineering and Bioprospecting’, this chapter).
Screen for a diversity of enzymes in a microbial community. This process, metagenomics, is a creative approach in screening for a diversity of enzymes and is close to the idea of screening a biodiversity library. It is thought to be an elegant strategy in light of the fact that it does not rely on the cultivation of microorganisms, but instead on DNA or mRNA that is directly isolated from an environmental sample, purified, digested, and cloned into suitable cloning vectors to construct complex environmental libraries. These gene libraries are screened using either sequence-based techniques or activity assays. Ideally, cultivation-independent approaches enable microbiologists to fully exploit the biological potential of a microbial community in its totality (Streit and Schmitz 2004).
While production of marine and microbe-based natural products via laboratory synthesis and genetically engineered approaches gets around the need to re-supply samples, the complexity of the molecular structure of compounds and the cutting-edge techniques employed will, no doubt, continue to present their own formidable challenges and limitations. Therefore, in many cases the only re-supply alternative will come from the cultivation and/or recollection of the organism itself under ABS agreements.
In any case, providers of genetic resources should seek to have access to the know-how and equipment needed to re-supply biological samples through any of the scientific technologies described above. In addition ABS agreements that involve supplying live samples of microbes and other organisms must be carefully evaluated because the sample itself is sufficient to provide endless quantities of the active compound or natural product in most cases. Contractual provisions should be negotiated in order to obtain as much information as possible regarding the future use of these samples. This includes reporting and auditing protocols. Also it must be emphasized that the country is the owner of samples and it should be compensated in case of future benefits. If the organism can be cultured and useful genes can be identified and isolated there would not be any dependence on the original source, hence no need to re-supply or to negotiate prices per sample. On the positive side, this would prevent the environmental impact caused by collecting large amounts of the resource in its original habitat.
As underscored above, the total synthesis or semi-synthesis of a drug may be possible, nevertheless the structural and stereochemical complexity of most natural compounds often preclude the development of economically feasible large-scale total syntheses. Similarly, pursuing the development of natural products derived from gene clusters or from microbes grown in lab conditions through synthetic biology and other genetic engineering techniques can be a dead-end initiative. In most cases these are knowledge intensive and multi-year-long enterprises (see section ‘Genetic Engineering and Bioprospecting’, this chapter). Nevertheless, there are companies that have successfully applied these cutting edge technologies for the development of natural products (Brush and Carrizosa 2004).
Cutting edge technologies used in the activities described in this Chapter are expensive and difficult for developing countries and their scientific bodies to obtain. Indeed, if those technologies are closely held and used exclusively by the user, may be completely inaccessible for use by countries that provide genetic resources, even if other capacity issues were not a barrier to direct laboratory bioprospecting. Nevertheless, non-proprietary gene and molecular technology is being transferred to providers of genetic resources in the form of protocols, equipment, and training negotiated in the context of ABS agreements (see Costa Rican, NCI and Panama chapters, this volume). For example, since 1991 INBio has increased its capacity by negotiating technology transfer and training provisions with partners such as Phytera, Diversa Corporation, the International Cooperative Biodiversity Groups (ICBG), the Global Environment Facility (GEF), Merck & Co, and the Costa Rica-United States of America Foundation for Cooperation. Consequently, INBio has been able to establish the following laboratories that provide important added value to present and future bioprospecting ventures:
Plant biotechnology laboratory: carries out sterilization procedures, preparation of media, includes transference and culture rooms used for micro-propagation of plant material.
Molecular biology laboratory: performs DNA extraction and PCR.
Microbiology laboratory: provides isolation and culture of bacteria and actinomycetes.
Mycology laboratory: carries out activities that range from isolation to taxonomic identification of fungus.
Chemical laboratory: carries out extraction, fractionation (BioXplore Technology), and nuclear magnetic resonance services.
Informatics unit: provides tailor-made databases according to each agreement (BioXplore Technology) (see Costa Rican Chapter No. 5, this volume).
INBio's relationship with users of genetic resources has definitely set a precedent followed by other providers of genetic resources. For example, the Panamanian ICBG (see Chapter No. 7, this volume) shows that local organizations have gained access to novel biotechnologies for bioassays and nonradioactive visualizing techniques. These technologies have allowed these organizations to carry out experiments almost independently of a large laboratory and supply-chain infrastructure, making them ‘portable’ or analogous to ‘field techniques’. Ten years ago, such technology was not so portable. In Panama, this technology has made it possible for support for the training and outfitting of in-country scientists through negotiated ABS agreements. Ten years ago, the emphasis would have been more on up-front payments or royalties, because trained Panamanian scientists and parascientists wouldn't have had a place to work in Panama. The Costa Rican and Panamanian experiences are clear examples of how the impact of science and technology affect the options available to negotiators of ABS agreements.
One of the greatest challenges in exploiting the enormous potential benefits of marine and terrestrial natural products is the difficulty in finding sustainable means of production for compounds of interest. Achieving this goal, however, may create an increased difficulty for providers seeking to ensure that users obtain ABS permissions, and share benefits arising from genetic resources that originated in their country. Having sustainable supplies is critical if a chemical is to be marketed as a drug, agrochemical, or other product. Reliable production is also a necessity to support the research needed to study and understand novel compounds before commercial potential can even be evaluated. Today, important developments in chemistry, molecular biology, and genomics provide a comprehensive menu of technologies that address supply and product development issues and contribute to the identification of microbial samples. Furthermore, technologies that mutate genes in order to develop new products (see section ‘Harvesting the Potential of Microorganisms Through Site-Directed Mutagenesis’, this chapter) should raise not only monetary but also ethical concerns among providers of genetic resources. These scientific and technological developments should influence the negotiation of supply, benefit-sharing, monitoring, and other relevant provisions of present and future ABS agreements.
Pharmaceutical and biotechnology companies seeking access to work with microbes are also provoking the anxiety of source countries over samples that do not require re-supply for development. There is no longer the control point that results from the need to recollect. In plants the ability to do synthetic biology raises similar concerns (see section ‘Generating Chemical Diversity through Bioprospecting and Synthetic Biology’, this chapter). Furthermore, providers of genetic resources are concerned about potential income and technology-transfer opportunities lost to scientific endeavors such as Craig Venter's efforts to decode and complete genome sequences of organisms (information on Venter's research can be reviewed at http://www.jcvi.org/). There is also some concern that, by making this information public, these researchers are jeopardizing the ability of countries to protect the value of genetic resources over which they have undisputed sovereign rights. The implication of this is that the free international flow of gene sequences may ultimately make control of genetic resources irrelevant. Since these efforts will increase dramatically in the future, source countries may want to strengthen and accelerate efforts to take advantage of opportunities to develop local capacity in order use their genetic diversity before it becomes public and looses its economic potential.
Scientific and technological developments are also the core and competitive advantage of companies based in industrialized countries. These companies are concerned that their competitive edge will be compromised if proprietary bioassays, molecular biology approaches and genomic technologies, as well as the nature of any specific leads, or the financial terms of an agreement are shared with parties peripheral to the parties to ABS agreements. Consequently, transfer of technology to providers of genetic resources is unlikely to include state-of-the-art equipment and know-how. Nevertheless, many companies are willing to transfer basic gene technology which in contrast to natural-compound chemistry does not particularly require expensive investments in laboratory equipment.
Table 1 Selected marine natural compounds currently under development as drugs (Compiled from Fenical 2006, Maxwell 2005, Kijjoa and Sawangwong 2004, Proksch et al 2002 and 2003, Haefner 2003, and Faulkner 2000)
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1 Regional Technical Advisor for Biodiversity, United Nations Development Programme/Global Environmental Facility.
2 Today, most ex-situ collections have benefit-sharing obligations with the countries that provided their biological resources and these obligations usually extend to all users of these resources (Carrizosa 2004).
3 Combinatorial chemistry was born in the 1980s when Mario Geysen invented the pin method in which simultaneous synthesis of diversified peptides gave rise to the first combinatorial libraries.
4 Natural products are defined as chemical compounds derived from biological sources.
5 A review of the origin of drugs over a 22-year period (1981–2002) indicated that 60 and 75% of drugs in the areas of cancer and infectious diseases, respectively, are of natural origin (Newman et al. 2003).
8 On 11 June 1993, a joint venture agreement was signed between Griffith University and Astra Pharmaceuticals Pty Ltd, Sydney, Australia, a subsidiary of Astra AB of Sweden. Astra AB merged with pharmaceutical giant Zeneca in 1999 to form AstraZeneca. This joint venture is today known as AstraZeneca R&D Griffith University.
10 Australia (Museum of the Northern Territories, 2002), Bangladesh (Bangladesh National Herbarium, Dhaka, 1994), Cambodia (Forest and Wildlife Research Institute, Department of Forestry and Wildlife, Phnom Penh, 2000), Ecuador (The AWA Peoples Federation, 1993), Gabon (Centre National de la Recherche Scientifique et Technologique, Libreville, 1993), Ghana (University of Ghana, Legon, 1993), Laos (Research Institute of Medicinal Plants, Ministry of Public Health, Vientiane, 1998), Madagascar (Centre National D'Applications des Recherches Pharmaceutiques, Antananarivo, 1990), Palau (Government of Palau, 2002), Papua New Guinea (University of Papua New Guinea, Port Moresby, 2001), Philippines (Philippines National Museum, Manila, 1992), Sarawak-Malaysia (State Government of Sarawak, State Department of Forests, 1994 and Sarawak Biodiversity Center, 2002), Tanzania (Traditional Medicine Research Institute, Muhumbili University College of Health Sciences, University of Dar Es Salaam, 1991), and Vietnam (Institute of Ecology and Biological Resources, National Center for Natural Science and Technology, Hanoi, 1997).
11 These companies include: American Cyanamid Company, Anti-Cancer Inc, Bristol Myers-Squibb Pharmaceutical Research Institute, Diversa Corporation, Dow Agrosciences, Glaxo Wellcome, Eisai Pharmaceutical Research, INDENA SpA, Molecular Nature Ltd, Novartis Oncology, Phenomenome Discoveries Inc, Phytomedics Inc, Searle-Monsanto, and Wyeth Pharmaceuticals.
12 Argentina, Cameroon, Chile, Costa Rica, Fiji, Jamaica, Jordan, Kyrgyzstan, Laos, Madagascar, Mexico, Nigeria, Panama, Papua New Guinea, Philippines, Peru, Samoa, Surinam, Uzbekistan, and Vietnam.
13 In contrast, in the terrestrial environment, plants exceed animals with regard to the production of secondary metabolites (Proksch et al. 2003).
14 Organisms whose cells have chromosomes with nucleosomal structure and separated from the cytoplasm by a two membrane nuclear envelope and compartmentalization of a function in distinct cytoplasmic organelles.
15 This is a unique group of microorganisms. They appear to be living fossils, the survivors of an ancient group of organisms that bridged the gap in evolution between bacteria and the eukaryotes (multicellular organisms). The name archaea comes from the Greek archaios meaning ancient.
16 Members of Protista which is the kingdom of eukaryotic unicellular, colonial and multicellular (without tissue specialization) organisms. It includes the Protozoa, unicellular eukaryotic algae and some fungi (myxomycetes, acrasiales and oomycetes).
17 Classical breeding has traditionally used genes from wild ancestors of cultivated plants and animals to promote pest resistance and develop new and improved crop variations or livestock breeds.
18 Polyphasic taxonomy considers all available phenotypic and genotypic data of bacteria and integrates them in a consensus type of classification, framed in a general phylogeny derived from 16S rRNA sequence analysis. In some cases, the consensus classification is a compromise containing a minimum of contradictions. It is thought that the more parameters that will become available in the future, the more polyphasic classification will gain stability (Vandamme et al. 1996).
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