摘要
L-cysteine desulfhydrase(CD)plays an impor-tant 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-thiogalacto-pyranoside(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 proper-ties of the recombinant CD were characterized and its critical role involved in the L-cysteine biosynthetic pathway was also discussed.
基金
This work was supported by Grant no.30470053 from the National Natural Science Foundation of China and Grant no.05YFJZJC00900 from the Natural Science Foundation of Tianjin,China.
