Cloning of desulfurization genes from Gordona sp. CYKS1 and its expression in Escherichia coli

Abstract

Desulfurization genes were cloned from Gordona sp. CYKS1 and these genes were expressed in Escherichia coli under the heterologous promoters. Cloning of desulfurization genes were carried out by polymerase chain reaction (PCR) and their homology to previously cloned desulfurization genes of Rhodococcus sp. IGTS8 was 89%. The homology of deduced amino acids sequence was 86% in DszA, 86% in DszB, and 90% in DszC, respectively. Desulfurization genes were expressed in E. coli. Two recombinant plasmid containing desulfurization genes were constructed using inducible trc and constitutive Bacillus promoter. Nine E. coli strains were tested and 18 recombinant E. coli strains conferred with desulfurization activity were constructed. Batch and Fed-batch culture were carried out to produce desulfurization enzymes and DszA enzyme in fed-batch culture was produced in the form of inclusion body. In batch culture, about 10% of DBT was conversed to 2-HBP.