Spontaneous cleavage of proteins at serine and threonine is facilitated by zinc.
Wollongong, Australia. In Aging Cell, Feb 2016
NMR analysis indicated that the imidazole group co-ordinates zinc and that once zinc is co-ordinated, it can polarize the carbonyl group of the peptide bond in a manner analogous to that observed in the active site of the metalloexopeptidase, carboxypeptidase A. The hydroxyl side chain of Ser/Thr is then able to cleave the adjacent peptide bond.
[Coordination chemical studies on the zinc enzymes].
Fukuyama, Japan. In Yakugaku Zasshi, 2013
The metal dissociation constants of bovine carbonic anhydrase II, bovine carboxypeptidase A, rat aminopeptidase B, and rat dipeptidyl peptidase III were measured using metal buffer solutions.
Chapter 24: Anaphylaxis.
Chicago, United States. In Allergy Asthma Proc, 2012
The preformed mediators from mast cells include histamine, tryptase, carboxypeptidase A, and proteoglycans (heparin and chondroitin sulfates).
Mast cells can enhance resistance to snake and honeybee venoms.
Stanford, United States. In Science, 2006
We show, in contrast, that mast cells can significantly reduce snake-venom-induced pathology in mice, at least in part by releasing carboxypeptidase A and possibly other proteases, which can degrade venom components.