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 Perry, L. L.
Right arrow Articles by Zylstra, G. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Perry, L. L.
Right arrow Articles by Zylstra, G. J.

 Previous Article  |  Next Article 

Journal of Bacteriology, November 2007, p. 7563-7572, Vol. 189, No. 21
0021-9193/07/$08.00+0     doi:10.1128/JB.01849-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.

Cloning of a Gene Cluster Involved in the Catabolism of p-Nitrophenol by Arthrobacter sp. Strain JS443 and Characterization of the p-Nitrophenol Monooxygenase{triangledown}

Lynda L. Perry* and Gerben J. Zylstra

Biotechnology Center for Agriculture and the Environment, School of Environmental and Biological Sciences, Rutgers, The State University of New Jersey, New Brunswick, New Jersey 08901

Received 10 December 2006/ Accepted 13 August 2007

The npd gene cluster, which encodes the enzymes of a p-nitrophenol catabolic pathway from Arthrobacter sp. strain JS443, was cloned and sequenced. Three genes, npdB, npdA1, and npdA2, were independently expressed in Escherichia coli in order to confirm the identities of their gene products. NpdA2 is a p-nitrophenol monooxygenase belonging to the two-component flavin-diffusible monooxygenase family of reduced flavin-dependent monooxygenases. NpdA1 is an NADH-dependent flavin reductase, and NpdB is a hydroxyquinol 1,2-dioxygenase. The npd gene cluster also includes a putative maleylacetate reductase gene, npdC. In an in vitro assay containing NpdA2, an E. coli lysate transforms p-nitrophenol stoichiometrically to hydroquinone and hydroxyquinol. It was concluded that the p-nitrophenol catabolic pathway in JS443 most likely begins with a two-step transformation of p-nitrophenol to hydroxy-1,4-benzoquinone, catalyzed by NpdA2. Hydroxy-1,4-benzoquinone is reduced to hydroxyquinol, which is degraded through the hydroxyquinol ortho cleavage pathway. The hydroquinone detected in vitro is a dead-end product most likely resulting from chemical or enzymatic reduction of the hypothetical intermediate 1,4-benzoquinone. NpdA2 hydroxylates a broad range of chloro- and nitro-substituted phenols, resorcinols, and catechols. Only p-nitro- or p-chloro-substituted phenols are hydroxylated twice. Other substrates are hydroxylated once, always at a position para to a hydroxyl group.

* Corresponding author. Present address: Department of Food Science, Purdue University, 745 Agriculture Mall Drive, West Lafayette, IN 47907-2009. Phone: (765) 496-3821. Fax: (765) 494-7953. E-mail: llperry{at}purdue.edu

{triangledown} Published ahead of print on 24 August 2007.

Journal of Bacteriology, November 2007, p. 7563-7572, Vol. 189, No. 21
0021-9193/07/$08.00+0     doi:10.1128/JB.01849-06
Copyright © 2007, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Zhang, J.-J., Liu, H., Xiao, Y., Zhang, X.-E., Zhou, N.-Y. (2009). Identification and Characterization of Catabolic para-Nitrophenol 4-Monooxygenase and para-Benzoquinone Reductase from Pseudomonas sp. Strain WBC-3. J. Bacteriol. 191: 2703-2710 [Abstract] [Full Text]  
  • Takeo, M., Murakami, M., Niihara, S., Yamamoto, K., Nishimura, M., Kato, D.-i., Negoro, S. (2008). Mechanism of 4-Nitrophenol Oxidation in Rhodococcus sp. Strain PN1: Characterization of the Two-Component 4-Nitrophenol Hydroxylase and Regulation of Its Expression. J. Bacteriol. 190: 7367-7374 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»