Manganese homeostasis in Bacillus subtilis is regulated by MntR, a bifunctional regulator related to the diphtheria toxin repressor family of proteins.

摘要: The Bacillus subtilis yqhN gene encodes a metalloregulatory protein distantly related to the Corynebacterium diphtheriae diphtheria toxin repressor (DtxR). While DtxR mediates iron-dependent repression of iron uptake, we demonstrate that (herein renamed mntR) manganese modulated regulator transport. An mntR mutant strain is sensitive both and cadmium, suggesting transport these metals derepressed. We selected Tn10 insertions suppress Mn(II) sensitivity or increase Cd(II) tolerance wild-type cells, in cases recovered mntH (formerly ydaR). MntH member NRAMP family proton-coupled, metal ion transporters. MntR also regulates expression ABC transporter (MntABCD). MntABCD transporters are selectively repressed by this regulation requires MntR. In high conditions, functions as Mn(II)-dependent transcription. contrast, acts positive mntABCD operon under low growth conditions. Biochemical studies binding control region Mn(II), while interaction with does not depend on Mn(II).