RNase E/G-dependent degradation of metE mRNA, encoding methionine synthase, in Corynebacterium glutamicum

Corynebacterium glutamicum is used for the industrial production of various metabolites, including L-glutamic acid and L-lysine. With the aim of understanding the post-transcriptional regulation of amino acid biosynthesis in this bacterium, we investigated the role of RNase E/G in the degradation of mRNAs encoding metabolic enzymes. In this study, we found that the cobalamin-independent methionine synthase MetE was overexpressed in ΔrneG mutant cells grown on various carbon sources. The level of metE mRNA was also approximately 6- to 10-fold higher in the ΔrneG mutant strain than in the wild-type strain. A rifampicin chase experiment showed that the half-life of metE mRNA was approximately 4.2 times longer in the ΔrneG mutant than in the wild-type strain. These results showed that RNase E/G is involved in the degradation of metE mRNA in C. glutamicum.