Send to

Choose Destination
See comment in PubMed Commons below
J Bacteriol. 1992 Apr;174(7):2059-64.

The mtrAB operon of Bacillus subtilis encodes GTP cyclohydrolase I (MtrA), an enzyme involved in folic acid biosynthesis, and MtrB, a regulator of tryptophan biosynthesis.

Author information

  • 1Department of Biological Sciences, Stanford University, California 94305.


mtrA of Bacillus subtilis was shown to be the structural gene for GTP cyclohydrolase I, an enzyme essential for folic acid biosynthesis. mtrA is the first gene in a bicistronic operon that includes mtrB, a gene involved in transcriptional attenuation control of the trp genes. mtrA of B. subtilis encodes a 20-kDa polypeptide that is 50% identical to rat GTP cyclohydrolase I. Increased GTP cyclohydrolase I activity was readily detected in crude extracts of B. subtilis and Escherichia coli in which MtrA was overproduced. Biochemical evidence indicating that MtrA catalyzes dihydroneopterin triphosphate and formic acid formation from guanosine triphosphate is presented. It was also shown that mtrB of B. subtilis encodes a 6-kDa polypeptide. Expression of mtrB is sufficient for transcriptional attenuation control of the B. subtilis trp gene cluster in Escherichia coli. Known interrelationships between genes involved in folic acid and aromatic amino acid biosynthesis in B. subtilis are described.

[PubMed - indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center