Novel three-finger toxins from Micrurus dumerilii and Micrurus mipartitus coral snake venoms: Phylogenetic relationships and characterization of Clarkitoxin-I-Mdum

Rey-Suárez P.; Saldarriaga-Córdoba M.; Torres U.; Marin-Villa M.; Lomonte B.; Núñez V.

Abstract

Micrurus mipartitus and M. dumerilii are the most medically important coral snakes in Colombia. Proteomic characterization of their venoms has previously shown that proteins of the three-finger toxin (3FTx) family are abundant components, especially in M. mipartitus (61%) and to a lesser extent in M. dumerilii (28%). In order to increase knowledge on these toxins, in this work a major 3FTx of M. dumerilii venom (8% of the venom proteins), named Clarkitoxin-I-Mdum, was isolated and characterized. Its amino acid sequence comprises 66 residues, with an isotope-averaged molecular mass of 7537 +/- 2 Da and a theoretical pl of 9.36, presenting the conserved pattern of eight cysteines that classifies it as a short-chain (type I) 3FTx. Clarkitoxin-I-Mdum was not lethal to mice by intravenous or intracerebroventricular route and was not cytolytic to myogenic cells in vitro. On the other hand, five coding sequences for 3FTxs were obtained from the venom gland of M. mipartitus. These novel toxin sequences were named Mm3FTx-01 to Mm3FTx-05, all of them also presenting the eight conserved cysteines of short-chain 3FTxs. Phylogenetic analysis revealed high variability of 3FTxs from Micrurus, and ELISA using antibodies raised to the major 3FTxs from M. mipartitus and M. dumerilii confirmed their immunochemical divergence. These results highlight the relevance of performing further studies aiming at a deeper understanding of the functional and antigenic relationships among specific Micrurus toxins, with important implications for the production of antivenoms.

Más información

Título según WOS: Novel three-finger toxins from Micrurus dumerilii and Micrurus mipartitus coral snake venoms: Phylogenetic relationships and characterization of Clarkitoxin-I-Mdum
Título según SCOPUS: Novel three-finger toxins from Micrurus dumerilii and Micrurus mipartitus coral snake venoms: Phylogenetic relationships and characterization of Clarkitoxin-I-Mdum
Título de la Revista: TOXICON
Volumen: 170
Editorial: PERGAMON-ELSEVIER SCIENCE LTD
Fecha de publicación: 2019
Página de inicio: 85
Página final: 93
Idioma: English
DOI:

10.1016/j.toxicon.2019.09.017

Notas: ISI, SCOPUS