Chymotrypsin C (caldecrin) promotes degradation of human cationic trypsin: identity with Rinderknecht's enzyme Y.

ABSTRACT: Digestive trypsins undergo proteolytic breakdown during their transit in the human alimentary tract, which has been assumed to occur through trypsin-mediated cleavages, termed autolysis. Autolysis was also postulated to play a protective role against pancreatitis by eliminating prematurely activated intrapancreatic trypsin. However, autolysis of human cationic trypsin is very slow in vitro, which is inconsistent with the documented intestinal trypsin degradation or a putative protective role. Here we report that degradation of human cationic trypsin is triggered by chymotrypsin C, which selectively cleaves the Leu(81)-Glu(82) peptide bond within the Ca(2+) binding loop. Further degradation and inactivation of cationic trypsin is then achieved through tryptic cleavage of the Arg(122)-Val(12

SUBMITTER: Szmola R 

PROVIDER: S-EPMC2040881 | biostudies-literature | 2007 Jul

REPOSITORIES: biostudies-literature