Primary Structure of H2-Proteinase, a Non-Hemorrhagic Metalloproteinase, Isolated from the Venom of the Habu Snake, Trimeresurus flavoviridis1

Abstract

The complete amino acid sequence of and the locations of disulfide bridges in H2-proteinase, a major non-hemorrhagic proteinase isolated from the venom of the habu Trimeresurus flavoviridis, have been determined and compared with those of HR2a, one of the hemorrhagic metalloproteinases in this venom. The strategy involved consisted of structural analysis of peptides in digests with cyanogen bromide, lysyl endopeptidase, trypsin, Staphylococcus aureus V8 protease and thermolysin. Peptides were purified by gel filtration followed by reversed-phase HPLC. H2-proteinase is a non-glycosylated single chain polypeptide consisting of 201 amino acids with an amino-terminal pyroglutamic acid, a calculated molecular weight of 22,991 and a net charge of +14 at neutral pH. There was no evidence of heterogeneity of the sequence. H2-proteinase has a typical zinc-chelating sequence and its overall sequence identity with HR2a is 73.6%. The 3 disulfide bridges in H2-proteinase link Cys-117 to Cys-196, Cys-158 to Cys-180, and Cys-160 to Cys-163, in the same manner as in the case of HR2a. In striking contrast to HR2a, it contains en extra free cysteine residue at position 94 which becomes reactive to a sulfhydryl reagent in the presence of a denaturant.

A [Lys49]phospholipase A2fromProtobothrops flavoviridisVenom Induces Caspase-Independent Apoptotic Cell Death Accompanied by Rapid Plasma-Membrane Rupture in Human Leukemia Cells

“…]phospholipase A 2 from Protobothrops flavoviridis Venom Induces Caspase-Independent Apoptotic Cell Death Accompanied by Rapid Plasma-Membrane Rupture in Human Leukemia Cells Snake venoms are complex mixtures of a number of physiologically active proteins including metalloproteases, 1,2) thrombin-like enzymes, 3,4) complement activating enzyme, 5) phospholipases A 2 (PLA 2 s) [EC 3.1. 1.4] 6,7) and so on.…”

Cloning and Identification of a Novel P-II Class Snake Venom Metalloproteinase from Gloydius halys

“…nlm.nih.gov/) according to the description in the original work. Seven snake nonhemorrhagic SVMPs [aclf (gi: 603215) [15], adm2 (640082) [2], bneu (gi: 6760464) [16], h2p (gi: 462303) [17], fibrolase (gi: 386076) [18], lebe (gi: 2118144) [19], and fibro (gi: 7428251) [20]] were selected from GenBank and entered into the BLOCKMAKER program [21], which is found at the CODEHOP website and is the first step in primer design. BLOCKMAKER is a multiple alignment program that identifies ungapped segments representing regions of proteins that are the most conserved.…”

Predicting the conformation of proteins man versus machine

“…For example, the same 7 hemorrhagic metalloproteases [41] yielded essentially identical multiple alignments when used individually as guide sequences. Yet the predictions yielded by the server were different.…”