title: Citrate inhibition of snake venom proteases.
abstract: Thirty snake venoms had a citrate content of 2.3 to 12.9%, dry basis, by an aconitase isocitric dehydrogenase coupled enzyme assay. This is a venom concentration range of approximately 30 to 150 mM citrate assuming 25% venom solids content. Inhibition of snake venom protease activity by the addition of exogenous citrate was obtained using azure blue hide powder and azocasein as substrates. Protease inhibitions of 7.5% for Crotalus atrox venom to 78% for Bothrops picadoi venom were observed with citrate. Complete inhibition of snake venom protease activity by citrate was not observed. Bothrops asper (Pacifico) venom showed a 41% protease inhibition by citrate with azocasein as the substrate and 46% inhibition of Bothrops asper (Alantico) venom protease with azure blue hide power as a substrate. Trypsin was not inhibited in this system. Citrate may inhibit some venom protease activity by forming a complex with the zinc of zinc-dependent enzymes. reserved.
authors.affiliation: Department of Biochemistry and Molecular Biology, School of Veterinary Medicine, Oklahoma State University, Stillwater 74078, USA.
authors.forename: G V
authors.initials: GV
authors.lastname: Odell
authors.forename: P C
authors.initials: PC
authors.lastname: Ferry
authors.forename: L M
authors.initials: LM
authors.lastname: Vick
authors.forename: A W
authors.initials: AW
authors.lastname: Fenton
authors.forename: L S
authors.initials: LS
authors.lastname: Decker
authors.forename: R L
authors.initials: RL
authors.lastname: Cowell
authors.forename: C L
authors.initials: CL
authors.lastname: Ownby
authors.forename: J M
authors.initials: JM
authors.lastname: Gutierrez
mesh_terms: D000818:Animals; D001399:Azure Stains; D002364:Caseins / Q000187:drug effects; D019343:Citric Acid / Q000032:analysis / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D011480:Protease Inhibitors / Q000494:pharmacology*; D012910:Snake Venoms / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D014357:Trypsin / Q000187:drug effects
chemical_list: D001399:Azure Stains; D002364:Caseins; D004791:Enzyme Inhibitors; D011480:Protease Inhibitors; D012910:Snake Venoms; C026018:azocasein; D019343:Citric Acid; D014357:Trypsin