JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
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 HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Aneja, P.
Right arrow Articles by Charles, T. C.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Aneja, P.
Right arrow Articles by Charles, T. C.

Journal of Bacteriology, February 1999, p. 849-857, Vol. 181, No. 3
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Poly-3-Hydroxybutyrate Degradation in Rhizobium (Sinorhizobium) meliloti: Isolation and Characterization of a Gene Encoding 3-Hydroxybutyrate Dehydrogenase

P. Aneja1 and T. C. Charles1,2,*

Department of Natural Resource Sciences, McGill University, Ste-Anne-de-Bellevue, Quebec, Canada H9X 3V9,1 and Department of Biology, University of Waterloo, Waterloo, Ontario, Canada N2L 3G12

Received 26 August 1998/Accepted 23 November 1998

We have cloned and sequenced the 3-hydroxybutyrate dehydrogenase-encoding gene (bdhA) from Rhizobium (Sinorhizobium) meliloti. The gene has an open reading frame of 777 bp that encodes a polypeptide of 258 amino acid residues (molecular weight 27,177, pI 6.07). The R. meliloti Bdh protein exhibits features common to members of the short-chain alcohol dehydrogenase superfamily. bdhA is the first gene transcribed in an operon that also includes xdhA, encoding xanthine oxidase/dehydrogenase. Transcriptional start site analysis by primer extension identified two transcription starts. S1, a minor start site, was located 46 to 47 nucleotides upstream of the predicted ATG start codon, while S2, the major start site, was mapped 148 nucleotides from the start codon. Analysis of the sequence immediately upstream of either S1 or S2 failed to reveal the presence of any known consensus promoter sequences. Although a sigma 54 consensus sequence was identified in the region between S1 and S2, a corresponding transcript was not detected, and a rpoN mutant of R. meliloti was able to utilize 3-hydroxybutyrate as a sole carbon source. The R. meliloti bdhA gene is able to confer upon Escherichia coli the ability to utilize 3-hydroxybutyrate as a sole carbon source. An R. meliloti bdhA mutant accumulates poly-3-hydroxybutyrate to the same extent as the wild type and shows no symbiotic defects. Studies with a strain carrying a lacZ transcriptional fusion to bdhA demonstrated that gene expression is growth phase associated.

* Corresponding author. Mailing address: Department of Biology, University of Waterloo, 200 University Ave. West, Waterloo, ON, Canada N2L 3G1. Phone: (519) 888-4576, ext. 5606. Fax: (519) 746-0614. E-mail: tcharles{at}uwaterloo.ca.

Journal of Bacteriology, February 1999, p. 849-857, Vol. 181, No. 3
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.


This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 1999 by the American Society for Microbiology. All rights reserved.