Psedomonas is which type of bacteria -
Ans. is 'c' i.e., Strict aerobe o Pseudomonas is an obligate aerobe (strict aerobe).Oxygen requirement of bacteriao Different bacteria have different oxygen requirment.o Why is it so ? Lets seeMolecular oxygen is very reactive .When it accepts an electron in electron transport chain, it can form H2O2, superoxide radicals (O2-) and a hydroxyl radical (OH-).All of these are toxin unless broken down.There are three enzymes : catalase, peroxidase and superoxide dismutase which can break down these oxygen radicals and can prevent bacteria from oxidative damage, i.e. these three enzymes defend bacteria from oxidative damage.The bacteria which possess all three enzymes are most oxygen tolerant, the bacteria which have one or two enzyme are less oxygen tolerant, while the bacteria which have no enzyme can not tolerat oxygen.Based on oxygen requirement the bacteria are classified into -Obligate aerobeso They grow only in aerobic conditions.o These bacteria have all the three enzymes and they have electron transport chain as the final electron acceptor,o Obligate aerobes are -1 Nocardia3. Mycobacteria 5. Pseudomonas7. Legionella2. Bacillus cereus4. Meningococci6. Bordetella 8. Brucella Facultative anaerobeso They prefer aerobic conditions, but can also grow in anaerobic conditions.o They are similar to obligate aerobes, i.e. they have all the enzymes.o The only difference is that they can grow in the absence of oxygen by using fermentation of energy,o Facultative anaerobes are1. Staphylococcus4. Corynebacterium7. Mycoplasma10. Salmonella2. Bacillus anthracis5. Listeria8. E. coli 3. Listeria6.Actinomyces9. Shigella Microaerophilic (aerotolerant anaerobes)o They prefer anaerobic conditions, but can tolerate low amounts of oxygen because they have superoxide dismutase (but they have no catalase),o Microaerophilic bacteria are -StreptococcusSpirochetes - Treponema, Borrelia, LeptospiraCampylobacterObligate anaerobeso They have no enzymes to defend against oxygen.o They grow only in anaerobic environment and can not tolerate aerobic conditions.o Obligate anaerobes are -1. Clostridium 2. Bacteroides
Anaerobic
Microaerophilic
Strict aerobe
Obligate anaerobe
Bacteria