This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by McFall, E
Right arrow Articles by Palchaudhuri, S
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by McFall, E
Right arrow Articles by Palchaudhuri, S

 Previous Article  |  Next Article 

J Bacteriol. 1991 February; 173(3): 1161-1167

research-article

Effects of structural changes in the dsdA-dsdC intergenic region on D-serine deaminase synthesis.

E McFall, S S Nikam and S Palchaudhuri

Department of Microbiology, New York University School of Medicine, New York 10016.

ABSTRACT

Single-base-pair changes well upstream of its transcription initiation site resulted in partially to fully constitutive expression of the D-serine deaminase structural gene, dsdA, independently of the cyclic AMP-cyclic AMP-binding protein complex and of the specific D-serine deaminase activator protein. These promoter mutations appear to define a consensus sequence that is repeated several times. Basal expression of dsdA+ was also strongly enhanced by subcloning on multicopy plasmids, by the DNA gyrase inhibitor novobiocin, and in dsdC(Con) mutants by increasing growth temperature. These results suggest that activation of dsdA+ expression by the dsdC-encoded protein involves distortion of promoter DNA. A dsdA translation start at bp -731 was verified by subcloning of dsdC+. Plasmid-specified activator at a high concentration interfered with chromosomal dsdC(Con) expression, and the interference was enhanced by deletion of most of the intergenic region from the plasmid. Even at a high concentration, however, plasmid-specified activator did not activate expression of chromosomal dsdA+, and in one case it was actually repressive. These results confirm the strong cis tropism of plasmid-specified dsdC-encoded protein and suggest that it is mediated by multiple sites in the dsdA-dsdC intergenic region.


J Bacteriol. 1991 February; 173(3): 1161-1167