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 Collier, L. S.
Right arrow Articles by Neidle, E. L.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Collier, L. S.
Right arrow Articles by Neidle, E. L.

J Bacteriol, May 1998, p. 2493-2501, Vol. 180, No. 9
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Regulation of Benzoate Degradation in Acinetobacter sp. Strain ADP1 by BenM, a LysR-Type Transcriptional Activator

Lauren S. Collier,1 George L. Gaines III,2 and Ellen L. Neidle1,*

Department of Microbiology, University of Georgia, Athens, Georgia 30602-2605,1 and Isogenetics, Inc., Chicago, Illinois 606122

Received 24 October 1997/Accepted 27 February 1998

In Acinetobacter sp. strain ADP1, benzoate degradation requires the ben genes for converting benzoate to catechol and the cat genes for degrading catechol. Here we describe a novel transcriptional activator, BenM, that regulates the chromosomal ben and cat genes. BenM is homologous to CatM, a LysR-type transcriptional activator of the cat genes. Unusual regulatory features of this system include the abilities of both BenM and CatM to recognize the same inducer, cis,cis-muconate, and to regulate some of the same genes, such as catA and catB. Unlike CatM, BenM responded to benzoate. Benzoate together with cis,cis-muconate increased the BenM-dependent expression of the benABCDE operon synergistically. CatM was not required for this synergism, nor did CatM regulate the expression of a chromosomal benA::lacZ transcriptional fusion. BenM-mediated regulation differs significantly from that of the TOL plasmid-encoded conversion of benzoate to catechol in pseudomonads. The benM gene is immediately upstream of, and divergently transcribed from, benA, and a possible DNA binding site for BenM was identified between the two coding regions. Two mutations in the predicted operator/promoter region rendered ben gene expression either constitutive or inducible by cis,cis-muconate but not benzoate. Mutants lacking BenM, CatM, or both of these regulators degraded aromatic compounds at different rates, and the levels of intermediary metabolites that accumulated depended on the genetic background. These studies indicated that BenM is necessary for ben gene expression but not for expression of the cat genes, which can be regulated by CatM. In a catM-disrupted strain, BenM was able to induce higher levels of catA expression than catB expression.


* Corresponding author. Mailing address: Department of Microbiology, University of Georgia, 527 Biological Sciences Building, Athens, GA 30602-2605. Phone: (706) 542-2852. Fax: (706) 542-2674. E-mail: eneidle{at}uga.cc.uga.edu.


J Bacteriol, May 1998, p. 2493-2501, Vol. 180, No. 9
0021-9193/98/$04.00+0
Copyright © 1998, 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 © 1998 by the American Society for Microbiology. All rights reserved.