Vm24 Scorpion Toxin

From Proteopedia

Revision as of 16:41, 26 April 2020

Introduction

Vm24 synthetic scorpion toxin is a peptide toxin isolated from Vaejovis mexicanus scorpion venom. It is a potent inhibitor of Kv1.3 potassium channels of human T lymphocytes. Its high affinity and specificity for human lymphocytes makes it a candidate for the treatment of several autoimmune disorders.

APBS Electrostatic Surface of Vm24, 2k9o

Protein Source

Gurolla G.B et al [1] isolated the peptide components of Vaejovis mexicanus smithi venom using high-performance liquid chromatography. Over 200 components were identified. The structure of Vm24 was determined by solution NMR spectroscopy, and it was sequenced via trypsin digestion. The a synthetic Vm24 gene was created and artificially translated to produce the synthetic Vm24 toxin displayed.

General Structure

Vm24 is a single chain protein consisting of 36 amino acids. It has a molecular weight of 3,873 daltons. It consists of a three strand (S1,S2,S3) anti-parallel and one single turn with holding the chain together. The disulfides exist between , , , and . The disulfide bonds between and with the C-terminal strand of the β-sheet. The disulfide bridge between connects the The abundant disulfides in this protein are highly important in conferring it's unusual, strained conformation [2]. Positions and are not well defined because they have a reduced number of Nuclear Overhauser effects NOEs [3] All and are buried entirely, but all other residues are exposed. and are in a very flexible region, which is interesting because they are adjacent to a .

Function

Vm24 is a potent and selective inhibitor of Kv1.3 potassium channels of human T lymphocytes. In vitro, Kv1.3 current is reduced by approximately 2/3 _{rds in the presence of 3pM of Vm24}