Establishment of a genetic transformation system and its application in Thermoanaerobacter tengcongensis

The whole-genome sequence of Thermoanaerobacter tengcongensis, an anaerobic thermophilic bacterium isolated from the Tengchong hot spring in China, was completed in 2002. However, in vivo studies on the genes of this strain have been hindered in the absence of genetic manipulation system. In order to establish such a system, the plasmid pBOL01 containing the replication origin of the T. tengcongensis chromosome and a kanamycin resistance cassette, in which kanamycin resistance gene expression was controlled by the tte1482 promoter from T. tengcongensis, was constructed and introduced into T. tengcongensis via electroporation. Subsequently, the high transformation efficiency occurred when using freshly cultured T. tengcongensis cells without electroporation treatment, suggesting that T. tengcongensis is naturally competent under appropriate growth stage. A genetic transformation system for this strain was then established based on these important components, and this system was proved to be available for studying physiological characters of T. tengcongensis in vivo by means of hisG gene disruption and complementation.