Proteomic characterization of the venom and transcriptomic analysis of the venomous gland from the Mexican centipede Scolopendra viridis

Abstract

This communication reports the results of proteomic, transcriptomic, biochemical and electrophysiological analysis of the soluble venom and venom glands of the Mexican centipede Scolopendra viridis Say (here thereafter abbreviated S. viridis). Separation of the soluble venom permitted to obtain 54 different fractions, from which a mass finger printing analysis permitted the identification of at least 86 components, where 70% of the molecules have low molecular masses. Two-dimensional electrophoretic separation of this venom revealed the presence of about forty proteins with molecular weights ranging from 17 to 58kDa. The novo sequencing of 149 peptides obtained by LC-MS/MS from the 2D-gels showed the presence of proteins with amino acid sequences similar to several enzymes and venom allergens type 3. Furthermore, a total of 180 sequences were obtained from a cDNA library prepared with two venomous glands. From this, 155 sequences correspond to complete genes containing more than 200 base pairs each. Comparative sequence analyses of these sequences indicated the presence of different types of enzymes and toxin-like genes. Two proteins with molecular weights around 37,000 and 42,000Da were shown to contain hyaluronidase activity. Electrophysiological assays performed with soluble venom show that it decreases mammalian sodium channel currents.

Biological significance: Animal venoms of Scolopendra species have been scarcely studied, although they have been reported to contain several bioactive compounds, some of which with potential therapeutic interest. The Mexican centipede S. viridis contains a powerful venom, capable of inflicting immediate effects on their preys. This communication is focused on the identification and description of a proteomic and transcriptomic analysis of the protein components of this venom. Several amino acid sequences similar to reported enzymes are the principal components in the S. viridis venom, but also a low number of toxins were identified. This knowledge should contribute to the understanding of the pharmacological effects caused by bites of this centipede species.

Keywords: De novo sequencing; Proteome; Scolopendra; Transcriptome; Venom; cDNA library.