Análise proteômica parcial da peçonha do escorpião colombiano Centruroides margaritatus (Gervais, 1841)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2008

RESUMO

Scorpion venoms are a complex mixture of peptides that exert their action via ion-channel modulation in biological membranes. The central objective of this project was to perform the proteomic characterization of the venom from the Colombian scorpion Centruroides margaritatus. This species is capable of producing moderate accidents and serious complications in humans, but little information is available related to its components. The venom was obtained by mild electrical stimulation method, applying 5 impulses of 50 V in each scorpion. It was observed differences in the production of the venom between males and females and also between pregnant and not-pregnant females. The crude venom was fractioned by RP-HPLC using a C8 column (4.6 x 250 mm) and 43 fractions were collected and vacuum dried. All these fractions were analyzed by MALDI-TOF/MS and 91 distinct compounds had their molecular masses characterized. The venom of C. margaritatus exhibits 54% of their toxins in the molecular mass range from 2.5 to 6.0 kDa that probably includes short-chain K+ channel blockers; 13% of the total are in the range from 6.5 to 8.0 kDa and may include long-chain Na+ channel toxins. Finally, 33% of the components present in C. margaritatus venom are peptides smaller than 2.0 KDa, a group rarely described in scorpions venoms. Two novel peptides were purified and chemically characterized: margatoxin 2 (MgTx2), 24 amino acids long (MM = 2,6 kDa) and three disulfide bridges, belonging to the -KTx family and margatoxin 3 (MgTx3), 30 amino acids long (MM = 3,38 kDa) and three disulfide bridges, with no significant similarities to other scorpion neurotoxins described.

ASSUNTO(S)

ciencias biologicas análise prateômica peçonha centruroides margaritatus

ACESSO AO ARTIGO

Documentos Relacionados