Biologically important proteins
· Glutathione is a tripeptide containing glutamic acid, cysteine and glycine. It is present in erythrocytes and several other tissues. It acts as a coenzyme and protects haemoglobin against oxidation.
· Insulin and glucagon are pancreatic hormones, involved in the regulation of glucose metabolism.
· Angiotensin is a peptide which stimulates the release of certain hormones from adrenal gland.
· Collagen, is a connective tissue protein rich in proline and hydroxy proline.
Plasma consists of many proteins such as albumin, globulin and fibrinogen. Total protein of the plasma is about 6-8gm /100ml. Plasma proteins comprise a major part of the solids of plasma. Albumin combine with substances of low solubilities such as cholesterol, triacylglycerol to form more soluble complexes, which can be transported in an aqueous environment of the body fluids.