Characterization of a Corynebacterium glutamicum lactate utilization operon induced during temperature-triggered glutamate production.

ABSTRACT: Gene expression changes of glutamate-producing Corynebacterium glutamicum were identified in transcriptome comparisons by DNA microarray analysis. During glutamate production induced by a temperature shift, C. glutamicum strain 2262 showed significantly higher mRNA levels of the NCgl2816 and NCgl2817 genes than its non-glutamate-producing derivative 2262NP. Reverse transcription-PCR analysis showed that the two genes together constitute an operon. NCgl2816 putatively codes for a lactate permease, while NCgl2817 was demonstrated to encode quinone-dependent l-lactate dehydrogenase, which was named LldD. C. glutamicum LldD displayed Michaelis-Menten kinetics for the substrate l-lactate with a K(m) of about 0.51 mM. The specific activity of LldD was about 10-fold higher during growth on l-lact

SUBMITTER: Stansen C 

PROVIDER: S-EPMC1265975 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature