Roles of PucR, GlnR, and TnrA in regulating expression of the Bacillus subtilis ure P3 promoter.
Expression of the P3 promoter of the Bacillus subtilis ureABC operon is activated during nitrogen-limited growth by PucR, the transcriptional regulator of the purine-degradative genes. Addition of allantoic acid, a purine-degradative intermediate, to nitrogen-limited cells stimulated transcription of ure P3 twofold. Since urea is produced during purine degradation in B. subtilis, regulation of ureABC expression by PucR allows purines to be completely degraded to ammonia. The nitrogen transcription factor TnrA was found to indirectly regulate ure P3 expression by activating pucR expression. The two consensus GlnR/TnrA binding sites located in the ure P3 promoter region were shown to be required for negative regulation by GlnR. Mutational analysis indicates that a cooperative interaction occurs between GlnR dimers bound at these two sites. B. subtilis is the first example where urease expression is both nitrogen regulated and coordinately regulated with the enzymes involved in purine transport and degradation.
Brandenburg
Jaclyn L
JL
Department of Microbiology, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
Wray
Lewis V
LV
Beier
Lars
L
Jarmer
Hanne
H
Saxild
Hans H
HH
Fisher
Susan H
SH
D001412:Bacillus subtilis / Q000235:genetics* / Q000254:growth & development; D001426:Bacterial Proteins / Q000378:metabolism*; D001483:Base Sequence; D003470:Culture Media; D004268:DNA-Binding Proteins; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009584:Nitrogen; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins; D015534:Trans-Activators / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D001426:Bacterial Proteins; D003470:Culture Media; D004268:DNA-Binding Proteins; C082451:GlnR protein, Streptomyces coelicolor; D012097:Repressor Proteins; C101458:ScgR protein, Bacillus subtilis; D015534:Trans-Activators; D014157:Transcription Factors; D009584:Nitrogen