Venom characterization of the three species of Ophryacus and proteomic profiling of O. sphenophrys unveils Sphenotoxin, a novel Crotoxin-like heterodimeric β-neurotoxin.

Autor: Neri-Castro E; Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Colonia Chamilpa, Cuernavaca, Morelos 62210, México; Programa de Doctorado en Ciencias Biomédicas UNAM, México., Lomonte B; Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José 11501, Costa Rica., Valdés M; Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Colonia Chamilpa, Cuernavaca, Morelos 62210, México; Laboratorio de Genética, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, 07738, México., Ponce-López R; Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Colonia Chamilpa, Cuernavaca, Morelos 62210, México., Bénard-Valle M; Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Colonia Chamilpa, Cuernavaca, Morelos 62210, México., Borja M; Facultad de Ciencias Biológicas, Universidad Juárez del Estado de Durango, Av. Universidad s/n. Fracc. Filadelfia, Gómez Palacio C.P. 35010, México., Strickland JL; Department of Biology, University of Central Florida, 4000 Central Florida Blvd, Orlando, FL 32816, USA., Jones JM; Herp.mx A.C., Villa del Álvarez, Colima, México., Grünwald C; Herp.mx A.C., Villa del Álvarez, Colima, México., Zamudio F; Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Colonia Chamilpa, Cuernavaca, Morelos 62210, México., Alagón A; Instituto de Biotecnología, Universidad Nacional Autónoma de México, Av. Universidad 2001, Colonia Chamilpa, Cuernavaca, Morelos 62210, México. Electronic address: alagon@ibt.unam.mx.
Jazyk: angličtina
Zdroj: Journal of proteomics [J Proteomics] 2019 Feb 10; Vol. 192, pp. 196-207. Date of Electronic Publication: 2018 Sep 08.
DOI: 10.1016/j.jprot.2018.09.002
Abstrakt: Venoms of the three species of Ophryacus (O. sphenophrys, O. smaragdinus, and O. undulatus), a viperid genus endemic to Mexico, were analyzed for the first time in the present work. The three venoms lacked procoagulant activity on human plasma, but induced hemorrhage and were highly lethal to mice. These venoms also displayed proteolytic and phospholipase A 2 activities in vitro. The venom of O. sphenophrys was the most lethal and caused hind-limb paralysis in mice. Proteomic profiling of O. sphenophrys venom showed a predominance of metalloproteinase (34.9%), phospholipase A 2 (24.8%) and serine protease (17.1%) in its composition. Strikingly, within its PLA 2 components, 12.9% corresponded to a Crotoxin-like heterodimer, here named Sphenotoxin, which was not found in the other two species of Ophryacus. Sphenotoxin, like Crotoxin, is composed of non-covalently bound A and B subunits. Partial amino acid sequence was obtained for Sphenotoxin B and was similar (78-89%) to other subunits described. The mouse i.v. LD 50 of Sphenotoxin at 1:1 M radio was 0.16 μg/g. Also, like Crotoxin, Sphenotoxin induced a potent neuromuscular blockade in the phrenic nerve-diaphragm preparation. Ophryacus is the fifth genus and O. sphenophrys the third non-rattlesnake species shown to contain a novel Crotoxin-like heterodimeric β-neurotoxin. BIOLOGICAL SIGNIFICANCE: Ophryacus is an endemic genus of semi-arboreal pitvipers from Mexico that includes three species with restricted distributions. Little is known about the natural history of these species and nothing is known about the properties of their venoms. Research on these species' venoms could generate relevant information regarding venom composition of Mexican pitvipers. Additionally, research into the presence of neurotoxic Crotoxin-like molecules outside of rattlesnakes (genera Crotalus and Sistrurus) has identified this molecule in several new genera. Knowing which genera and species possess neurotoxic components is important to fully understand the repercussions of snakebites, the interaction with prey and predators, and the origin, evolution, and phylogenetic distribution of Crotoxin-like molecules during the evolutionary history of pitvipers. Our study expands current knowledge regarding venom's compositions and function from Mexican pitvipers, providing a comparative venom characterization of major activities in the three Ophryacus species. Additionally, the discovery and characterization of a novel Crotoxin-like molecule, here named Sphenotoxin, in O. sphenophrys, and the detailed protein composition of O. sphenophrys venom supports the hypotheses that Crotoxin-like -β-neurotoxins are more widespread than initially thought.
(Copyright © 2018. Published by Elsevier B.V.)
Databáze: MEDLINE
Externí odkaz: