Cloning, expression and characterization of L-cysteine desulfhydrase gene from Pseudomonas sp. TS1138

Abstract

L-cysteine desulfhydrase (CD) plays an important role in L-cysteine decomposition. To identify the CD gene in Pseudomonas sp. TS1138 and investigate its effect on the L-cysteine biosynthetic pathway, the CD gene was cloned from Pseudomonas sp. TS1138 by polymerase chain reaction (PCR) method. The nucleotide sequence of CD gene was determined to be 1,215 bp, and its homology with other sequences encoding CD was analyzed. Then the CD gene was subcloned into pET-21a(+) vector and expressed in Escherichia coli (E. coli) by isopropyl-β-D-thiogalactopyranoside (IPTG) inducement. The recombinant CD was purified by Ni-NTA His-Bind resin, and its activity was identified by the CD activity staining. The enzymatic properties of the recombinant CD were characterized and its critical role involved in the L-cysteine biosynthetic pathway was also discussed.