The salmonella typhimurium gene factors involved in regulation of metE Gene

Enteric Salmonella is one of the food microbial pathogens. Among all the subspecies, Salmonella typhimurium LT2, of which chromosomal DNA has been sequenced and found out to be similar to that of Escherichia coli, is one of the major microorganisms for the current research study. Methionine biosynthesis is an essential metabolic pathway for bacterial growth. The final step for methionine biosynthesis is mediated by the metE-encoded MetE enzyme (cobalamin-independent methionine synthase). In this study, via constructing the Salmonella chromosomal DNA library, we identified the regulators of metE through a genome-wide screen. Our results revealed that the genes rseB, metB, ycjE, fabI, nifU, and nifS may encode the products that affect the expression of metE. These genes fall into catagories with a wide variety of cellular functions, suggesting the expression of metE as well as methionine biosynthesis may be under complicated regulations in enteric Salmonella. Furthermore, the gene-library based screening method used in this study is also likely to be applied for other related study.