Development of a sensitive gene expression reporter system and an inducible promoter-repressor system for Clostridium acetobutylicum

A sensitive gene expression reporter system was developed for Clostridium acetobutylicum ATCC 824 by using a customized gusA expression cassette. In discontinuous cultures, time course profiles of beta-glucuronidase specific activity reflected adequately in vivo dynamic up- and down-regulation of acidogenesis- and/or solventogenesis-associated promoter expression in C. acetobutylicum. Furthermore, a new inducible gene expression system was developed in C. acetobutylicum, based on the Staphylococcus xylosus xylose operon promoter-repressor regulatory system.