<unk>  is a glycoprotein found in the egg white and tissues of birds, reptiles and amphibians. It contains four identical subunits having a combined mass of 67,000-68,000 daltons. Each subunit consists of 128 amino acids and binds one molecule of biotin. The extent of glycosylation is very high. Carbohydrate accounts for about 10% of the total mass of<unk> .<unk>  has a basic isoelectric point (pI) of 10-10.5 and is stable over a wide range of pH and temperature. Extensive chemical modification has little effect on the activity of<unk> , making it especially useful for protein purification. Because of its carbohydrate content and basic pI,<unk>  has relatively high nonspecific binding.
Avidin
Hemin
Hemocyanin
Suramin
Toxidrome
Biotin
Hemocoel
N-Acetylglutamic acid