Microb Genom. 2016 Oct 21;2(10):e000091. doi: 10.1099/mgen.0.000091. eCollection 2016.

Methionine-mediated gene expression and characterization of the CmhR regulon in Streptococcus pneumoniae.

Afzal M1, Shafeeq S2, Kuipers OP3.

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This study investigated the transcriptomic response of Streptococcus pneumoniae D39 to methionine. Transcriptome comparison of the S. pneumoniae D39 wild-type grown in chemically defined medium with 0-10 mM methionine revealed the elevated expression of various genes/operons involved in methionine synthesis and transport (fhs, folD, gshT, metA, metB-csd, metEF, metQ, tcyB, spd-0150, spd-0431 and spd-0618). Furthermore, β-galactosidase assays and quantitative RT-PCR studies demonstrated that the transcriptional regulator, CmhR (SPD-0588), acts as a transcriptional activator of the fhs, folD, metB-csd, metEF, metQ and spd-0431 genes. A putative regulatory site of CmhR was identified in the promoter region of CmhR-regulated genes and this CmhR site was further confirmed by promoter mutational experiments.


CmhR; MetE; MetQ; Methionine; Pneumococcus

PMID: 28348831 PMCID: PMC5359408 DOI: 10.1099/mgen.0.000091