화학공학소재연구정보센터
Protein Expression and Purification, Vol.82, No.2, 325-331, 2012
Recombinant expression, purification, and characterization of scorpion toxin Bm alpha TX14
Long-chain and cysteine-rich scorpion toxins exhibit various pharmacological profiles for different voltage-gated sodium channel subtypes. However, the exploration of toxin structure-function relationships has progressed slowly due to the difficulty of obtaining synthetic or recombinant peptides. We now report that we have established an effective expression and purification approach for the novel scorpion toxin Bm alpha TX14. Bm alpha TX14 was over-expressed as inclusion bodies in Escherichia coli. The insoluble pellet was successfully transformed into active peptide by using a refolding procedure. One-step purification by reverse-phase HPLC was sufficient to generate chromatographically pure peptide. The yield of recombinant toxin reached 4 mg from 1 L LB medium. The pharmacological data further showed that Bm alpha TX14 selectively inhibited the fast inactivation of mNa(v)1.4 (EC50 = 82.3 +/- 15.7 nM) rather than that of rNa(v)1.2 (EC50 > 30 mu M), which indicates that Bm alpha TX14 is a new alpha-like toxin. This work enables further structural, functional, and pharmacological studies of Bm alpha TX14 and similar toxins. (C) 2012 Elsevier Inc. All rights reserved.