proteolytic enzyme

proteolytic enzyme

enzyme
also called  Proteinase,  

      any of a group of enzymes that break the long chainlike molecules of proteins into shorter fragments (peptides) and eventually into their components, amino acids. Proteolytic enzymes are present in bacteria and plants but are most abundant in animals. In the stomach, protein materials are attacked initially by the gastric enzyme pepsin. When the protein material is passed to the small intestine, proteins, which are only partially digested in the stomach, are further attacked by proteolytic enzymes secreted by the pancreas.

      These enzymes are liberated in the small intestine from inactive precursors produced by the acinar cells in the pancreas. The precursors are called trypsinogen, chymotrypsinogen, proelastase, and procarboxypeptidase. When the pancreatic enzymes become activated in the intestine, they convert proteins into free amino acids, which are easily absorbed by the cells of the intestinal wall.

      Trypsinogen is transformed to trypsin by an enzyme (enterokinase) secreted from the walls of the small intestine. Trypsin then activates the precursors of chymotrypsin, elastase, and carboxypeptidase.

      The pancreas produces a protein that inhibits trypsin. It is thought that in this manner the pancreas protects itself from autodigestion.

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Universalium. 2010.

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  • proteolytic enzyme — proteolytic enzyme. См. пептидаза. (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • proteolytic enzyme — proteolytic enzyme. = peptidase (см.). (Источник: «Англо русский толковый словарь генетических терминов». Арефьев В.А., Лисовенко Л.А., Москва: Изд во ВНИРО, 1995 г.) …   Молекулярная биология и генетика. Толковый словарь.

  • proteolytic enzyme — proteazė statusas T sritis chemija apibrėžtis Fermentas, katalizuojantis peptidinių ryšių hidrolizę. atitikmenys: angl. protease; proteolytic enzyme rus. протеаза; протеолитический фермент ryšiai: sinonimas – proteolitinis fermentas …   Chemijos terminų aiškinamasis žodynas

  • proteolytic enzyme — noun any enzyme that catalyzes the splitting of proteins into smaller peptide fractions and amino acids by a process known as proteolysis • Syn: ↑protease, ↑peptidase, ↑proteinase • Hypernyms: ↑enzyme • Hyponyms: ↑caspase, ↑ …   Useful english dictionary

  • proteolytic enzyme — a digestive enzyme that causes the breakdown of protein. See endopeptidase, exopeptidase. * * * peptidase …   Medical dictionary

  • proteolytic enzyme — a digestive enzyme that causes the breakdown of protein. See: endopeptidase, exopeptidase …   The new mediacal dictionary

  • proteolytic enzyme — See proteaseor peptidase …   Dictionary of molecular biology

  • enzyme analysis — ▪ diagnostics       in blood serum (serum), measurement (blood analysis) of the activity of specific enzymes (enzyme) in a sample of blood serum, usually for the purpose of identifying a disease. The enzymes normally are concentrated in cells and …   Universalium

  • proteolytic — Relating to or effecting proteolysis. SYN: proteoclastic. * * * pro·teo·lyt·ic .prōt ē ə lit ik adj of, relating to, or producing proteolysis <proteolytic enzymes> pro·teo·lyt·i·cal·ly i k(ə )lē adv * * * pro·teo·lyt·ic (pro″te o… …   Medical dictionary

  • enzyme — Synonyms and related words: beta amylase, carbohydrase, coenzyme, deoxyribonuclease, digestant, digester, digestive, esterase, holoenzyme, insulinase, lipase, lipoxidase, pepsin, polynucleotidase, protease, proteolytic enzyme, ribonuclease,… …   Moby Thesaurus

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