Utilization of lacZ to Isolate Regulatory Genes from Corynebacterium glutamicum

다국어 초록 (Multilingual Abstract)

A total of 100 Corynebacterial clones exerting a regulatory effect on the aceB promoter of Corynebacterium glutamicum were isolated by utilizing a reporter carrying the enteric lacZ gene fused to the promoter. The isolated clones were classified into 3 groups of A, B, and C, according to their color of colonies. Escherichia coli cells carrying clones in groups A and B showed a 90% and 50% reduction in β-galactosidase activity, respectively. The introduction of group A clones into C. glutamicum also resulted in an almost complete reduction in the expression of the aceA and aceB genes, suggesting that the clones express repressor-like proteins for the genes. Although white colonies were formed on plates containing X-gal, E. coli cells carrying one of the clones in group C exhibited intact β-galactosidase activity. The result suggests that the clone may encode proteins that prevent the cells from accumulating the chromogenic compound, X-gal.