Isolation and characterization of an endogenous inhibitor of phospholipase A(2) from Indian cobra (Naja naja naja) venom

摘要

A PLA(2)-inhibitor has been purified from Indian cobra (Naja naja naja) venom by the combination of ion-exchange and gel-filtration chromatography. The inhibitor, NN-I-3 was a peptide with mol.wt 6500 and has a fluorescence emission maxima cn 340 nm. NN-I-3 specifically inhibited the enzyme activity of the three acidic PLA? from the same venom. The inhibition of NN-I-2d-PLA(2) and NN-I-2e-PLA(2) by NN-I-3 was of mixed type and NN-I-2c-PLA(2) was of uncompetitive type, Neither the inhibitor nor the individual mixtures of acidic PLA(2) with the inhibitor (1:1 w/w or 1:2 mol:mol) were lethal to mice when injected intraperitoneally in doses up to 10 mgkg(-l) body weight. (C) 1998 Elsevier Science Ltd. All rights reserved. [References: 15]