The modE gene product mediates molybdenum-dependent expression of genes for the high-affinity molybdate transporter and modG in Azotobacter vinelandii.
The Azotobacter vinelandii mod locus, which is involved in high-affinity molybdate transport and the early event in Mo metabolism, consists of two divergently transcribed operons, modG and modEABC. modA, modB and modC encode the components of the high-affinity molybdate transporter, and modG encodes a Mo-binding protein. High concentrations of Mo repressed transcription of both operons. The modEABC operon was also repressed by tungstate and to a lesser extent by vanadate. modE, the first gene in the modEABC operon, controlled the Mo-dependent transcription of both operons. It was not involved in the metal regulation of alternative nitrogenase gene expression. Although a modE mutant constitutively expressed genes encoding the molybdate transporter, it had a reduced rate of Mo accumulation.
Mouncey
N J
NJ
Nitrogen Fixation Laboratory, University of Sussex, Brighton, UK.
Mitchenall
L A
LA
Pau
R N
RN
D016948:Azotobacter vinelandii / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins; D001483:Base Sequence; D002352:Carrier Proteins / Q000096:biosynthesis*; D003001:Cloning, Molecular; D017931:DNA Primers; D004926:Escherichia coli; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D005798:Genes, Bacterial; D005838:Genotype; D047908:Intracellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D008982:Molybdenum / Q000378:metabolism* / Q000494:pharmacology; D009876:Operon; D016133:Polymerase Chain Reaction; D017384:Sequence Deletion; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D002352:Carrier Proteins; D017931:DNA Primers; D029968:Escherichia coli Proteins; D047908:Intracellular Signaling Peptides and Proteins; C491064:ModE protein, E coli; C101050:ModE protein, bacteria; C101049:ModG protein, Azotobacter vinelandii; D014157:Transcription Factors; D008982:Molybdenum