The Fur-like protein Mur of Rhizobium leguminosarum is a Mn(2+)-responsive transcriptional regulator.
In wild-type Rhizobium leguminosarum, the sitABCD operon specifies a Mn(2+) transporter whose expression is severely reduced in cells grown in the presence of this metal. Mutations in the R. leguminosarum gene, mur (manganese uptake regulator), whose product resembles the Fur transcriptional regulator, cause high-level expression of sitABCD in the presence of Mn(2+). In gel-shift mobility assays, purified R. leguminosarum Mur protein bound to at least two regions near the sitABCD promoter region, although this DNA has no conventional consensus Fur-binding sequences (fur boxes). Thus, in contrast to gamma-proteobacteria, where Fur binds Fe(2+), the R. leguminosarum Fur homologue, Mur, act as a Mn(2)-responsive transcriptional regulator.
Díaz-Mireles
E
E
School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
Wexler
M
M
School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
Sawers
G
G
Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Colney Lane, Norwich NR4 7UH, UK.
Bellini
D
D
School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
Todd
J D
JD
School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
Johnston
A W B
AWB
School of Biological Sciences, University of East Anglia, Norwich NR4 7TJ, UK.
D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D027682:Cation Transport Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015964:Gene Expression Regulation, Bacterial; D007501:Iron / Q000378:metabolism; D008345:Manganese / Q000378:metabolism*; D008969:Molecular Sequence Data; D009876:Operon; D012097:Repressor Proteins / Q000378:metabolism*; D016961:Rhizobium leguminosarum / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D027682:Cation Transport Proteins; D012097:Repressor Proteins; C068477:ferric uptake regulating proteins, bacterial; D008345:Manganese; D007501:Iron