Crotalus durissus terrificus crotapotin naturally displays preferred positions for amino acid substitutions

Autor(es)

de Oliveira, Laudiceia Alves ^[1] ; Ferreira, Jr., Rui Seabra ^{[1, 2]} ; Barraviera, Benedito ^{[1, 2]} ; Tavares de Carvalho, Francilene Capel ^[1] ; de Barros, Luciana Curtolo ^[2] ; dos Santos, Lucilene Delazari ^{[1, 2]} ; Pimenta, Daniel Carvalho ^{[1, 3]}

Afiliação do(s) autor(es)

^[1] Sao Paulo State Univ UNESP, Botucatu Med Sch, Postgrad Program Trop Dis, Botucatu, SP - Brazil

^[2] Sao Paulo State Univ UNESP, Ctr Studies Venoms & Venomous Anim CEVAP, Botucatu, SP - Brazil

^[3] Butantan Inst, Lab Biochem & Biophys, Av Vital Brazil 1500, BR-05503900 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Venomous Animals and Toxins including Tropical Diseases; v. 23, NOV 28 2017.
• Citações Web of Science: 3

Resumo

Abstract Background Classically, Crotalus durissus terrificus (Cdt) venom can be described, according to chromatographic criteria, as a simple venom, composed of four major toxins, namely: gyroxin, crotamine, crotoxin and convulxin. Crotoxin is a non-covalent heterodimeric neurotoxin constituted of two subunits: an active phospholipase A2 and a chaperone protein, termed crotapotin. This molecule is composed of three peptide chains connected by seven disulfide bridges. Naturally occurring variants/isoforms of either crotoxin or crotapotin itself have already been reported. Methods The crude Cdt venom was separated by using RP-HPLC and the toxins were identified by mass spectrometry (MS). Crotapotin was purified, reduced and alkylated in order to separate the peptide chains that were further analyzed by mass spectrometry and de novo peptide sequencing. Results The RP-HPLC profile of the isolated crotapotin chains already indicated that the α chain would present isoforms, which was corroborated by the MS and tandem mass spectrometry analyses. Conclusion It was possible to observe that the Cdt crotapotin displays a preferred amino acid substitution pattern present in the α chain, at positions 31 and 40. Moreover, substitutions could also be observed in β and γ chains (one for each). The combinations of these four different peptides, with the already described chains, would produce ten different crotapotins, which is compatible to our previous observations for the Cdt venom. (AU)

• Processo FAPESP: 12/08101-8 - Imageamento in vivo da regeneração nervosa após reimplante de raízes motoras com selante de fibrina fluo-marcado associado com células tronco mesenquimais
• Beneficiário: Rui Seabra Ferreira Junior
• Modalidade de apoio: Auxílio à Pesquisa - Regular