Venomous extract protein profile of Brazilian tarantula Grammostola iheringi: searching for potential biotechnological applications.

UNLABELLED: Tarantula spiders, Theraphosidae family, are spread throughout most tropical regions of the world. Despite their size and reputation, there are few reports of accidents. However, like other spiders, their venom is considered a remarkable source of toxins, which have been selected through millions of years of evolution. The present work provides a proteomic overview of the fascinating complexity of the venomous extract of the Grammostola iheringi tarantula, obtained by electrical stimulation of the chelicerae. For analysis a bottom-up proteomic approach Multidimensional Protein Identification Technology (MudPIT) was used. Based on bioinformatics analyses, PepExplorer, a similarity-driven search tool that identifies proteins based on phylogenetically close organisms, a total of 395 proteins were identified in this venomous extract. Most of the identifications (~70%) were classified as predicted (21%), hypothetical (6%) and putative (37%), while a small group (6%) had no predicted function. Identified molecules matched with neurotoxins that act on ions channels; proteases, such as serine proteases, metalloproteinases, cysteine proteinases, aspartic proteinases, carboxypeptidases and cysteine-rich secretory enzymes (CRISP) and some molecules with unknown target. Additionally, non-classical venom proteins were also identified. Up to now, this study represents, to date, the first broad characterization of the composition of G. iheringi venomous extract. Our data provides a tantalizing insight into the diversity of proteins in this venom and their biotechnological potential. SIGNIFICANCE: Animal venoms contain a diversity of molecules able to bind to specific cell targets. Due to their biochemical and physiological properties, these molecules are interesting for medical and biotechnological purposes. In this study, a large number of components of the venomous extract of the spider Grammostola iheringi were identified by the MudPIT technique. It was demonstrated that this approach is a sensitive and adequate method to achieve a broad spectrum of information about animal venoms. Using this bottom-up proteomic method, classical and non-classical venom proteins were identified which stimulate new interest in the systematic research of their protein components.