Roland Montemayor, Texas A&M University – Kingsville

Expression, purification, and characterization of a new recombinant crotamine isoform from the venom gland of Crotalus oreganus helleri on antimicrobial activity

Abstract: Crotamine, a highly basic, non-enzymatic toxin, is the major toxic component found in the venom of the South American rattlesnake, Crotalus durissus terrificus. Based on the three-dimensional structure of crotamine, its cysteine-pairing pattern and folding structure is very similar to those of the other small toxins identified in different rattlesnake venoms and the antimicrobial peptide human β-defensins. Native, recombinant, and synthesized crotamine (YKQCHKKGGHCFPKEKICLPPSSDFGKMDCRWRWKCCKKGSG) has been found to contain antimicrobial activity against a wide variety of bacteria and fungi. In the present work, we aim to express recombinant crotamine-like protein, helleramine, cloned from the venom gland cDNA library of Crotalus oreganus helleri and to characterize its antimicrobial activity against Gram-negative and Gram-positive bacteria. Mature helleramine 6O01 cloned into pGEX-4T-1 vector (6O01-pGEX-4T-1), were expressed in Escherichia coli BL21. The N-terminus Glutathione S-transferase (GST)-tagged fusion protein was purified using Glutathione Sepharose 4B resins. Purified tag-cleaved recombinant helleramine will be further investigated for its antimicrobial activity. The production of recombinant helleramine with biological activity may provide new and powerful antimicrobial peptides as scaffolds for potential therapeutic development.

Presentation Author(s):
Roland Montemayor*

Judging Forms Official judges only