Pepsin is a type of

(D) Hydrolase# PEPSIN:> Pepsin is produced by the serous cells of the stomach as pepsinogen, the inactive zymogen or proenzyme.> Pepsin A is the most predominant gastric protease which preferentially cleaves peptide bonds formed by amino groups of phenylalanine or tyrosine or leucine.> Protease or Peptidase or Proteinase: is any enzyme that performs proteolysis; protein catabolism by hydrolysis of peptide bonds.> It break down the bonds by a process - hydrolysis and convert proteins into smaller chains - peptides or even smaller units - amino acids.> Pepsinogen is converted to active pepsin either by autocatalysis, brought about by other pepsin molecules or by gastric HCI (pH < 2).HYDROLASESPhospholipids-PhospholipaseLysophospholipidsLecithin - LysolecithinEnzymes Acting on Peptide Bonds:Exopeptidases-CarboxypeptidaseAiminoacidsEndopeptidase-Aminopeptidases(smallerpeptides)E.g.Pepsin > Removal of a fragment of polypeptide chain (44 amino acids in case of pig enzyme) makes the inactive enzyme active after attaining a proper conformation.> Pepsin is an acid-stable endopeptidase optimally active at a very low pH (2.0).> The active site of the enzyme contains two carboxyl groups, which are maintained at low pH.> Pepsin digestion of proteins results in peptides and a few amino acids which act as stimulants for the release of the hormone cholecystokinin from the duodenum.