Collection of regulogs for SahR/SamR transcription factor

Transcription factor SahR from the ArsR protein family regulates the methionine metabolism in Proteobacteria. The SahR regulon and its DNA-binding motif were discovered by application of the comparative genomic approach [24118949]. SahR contains N-terminal helix-turn-helix domain (HTH_ArsR, PF01022) presumably implicated in DNA binding and C-terminal SAM-dependent methyltransferase domain (PF01209) that is utilized in effector binding and dimerization. SahR functions as a negative regulator that responds to S-adenosylhomocysteine (SAH) and the SahR regulon often includes SAH recycling genes [24118949]. more

SamR is a distant homolog of SahR in the Xanthomonadales lineage of Gamma-proteobacteria, and its predicted binding motif partially resembles . the SahR binding motif. The recosntructed SamR regulon includes genes involved in the methionine and S-adenosylhomocysteine (SAM) biosynthesis. The SamR effector molecule remains to be determined, however the content of SamR regulons suggests that SamR responds to SAM rather to SAH effector.