98%
921
2 minutes
20
Comamonas sp. strain JS765 can grow with nitrobenzene as the sole source of carbon, nitrogen, and energy. We report here the sequence of the genes encoding nitrobenzene dioxygenase (NBDO), which catalyzes the first step in the degradation of nitrobenzene by strain JS765. The components of NBDO were designated Reductase(NBZ), Ferredoxin(NBZ), Oxygenase(NBZalpha), and Oxygenase(NBZbeta), with the gene designations nbzAa, nbzAb, nbzAc, and nbzAd, respectively. Sequence analysis showed that the components of NBDO have a high level of homology with the naphthalene family of Rieske nonheme iron oxygenases, in particular, 2-nitrotoluene dioxygenase from Pseudomonas sp. strain JS42. The enzyme oxidizes a wide range of substrates, and relative reaction rates with partially purified Oxygenase(NBZ) revealed a preference for 3-nitrotoluene, which was shown to be a growth substrate for JS765. NBDO is the first member of the naphthalene family of Rieske nonheme iron oxygenases reported to oxidize all of the isomers of mono- and dinitrotoluenes with the concomitant release of nitrite.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC126692 | PMC |
http://dx.doi.org/10.1128/AEM.68.2.634-641.2002 | DOI Listing |
Microb Biotechnol
March 2009
Department of Microbiology, College of Biological Sciences, University of California, Davis, CA 95616, USA.
Widespread application of chloronitrobenzenes as feedstocks for the production of industrial chemicals and pharmaceuticals has resulted in extensive environmental contamination with these toxic compounds, where they pose significant risks to the health of humans and wildlife. While biotreatment in general is an attractive solution for remediation, its effectiveness is limited with chloronitrobenzenes due to the small number of strains that can effectively mineralize these compounds and their ability to degrade only select isomers. To address this need, we created engineered strains with a novel degradation pathway that reduces the total number of steps required to convert chloronitrobenzenes into compounds of central metabolism.
View Article and Find Full Text PDFEnviron Sci Technol
July 2008
Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, 8092 Zurich, Switzerland.
Nitroaromatic compounds that contaminate soil and groundwater can be biodegraded by different, sometimes competing reaction pathways. We evaluated the combined use of compound-specific stable C and N isotope analysis to distinguish between enzymatic nitrobenzene oxidation by Comamonas sp. strain JS765 and partial reduction by Pseudomonas pseudoalcaligenes strain JS45 under aerobic conditions.
View Article and Find Full Text PDFJ Ind Microbiol Biotechnol
February 2007
USDA-ARS, New England Plant, Soil, and Water Laboratory, Orono, ME 04469, USA,
The catechol meta cleavage pathway is one of the central metabolic pathways for the degradation of aromatic compounds. A novel organization of the pathway genes, different from that of classical soil microorganisms, has been observed in Sphingomonas sp HV3 and Pseudomonas sp. DJ77.
View Article and Find Full Text PDFAppl Environ Microbiol
March 2006
Section of Microbiology, 226 Briggs Hall, 1 Shields Ave., University of California, Davis, CA 95616, USA.
Nitrobenzene 1,2-dioxygenase from Comamonas sp. strain JS765 catalyzes the initial reaction in nitrobenzene degradation, forming catechol and nitrite. The enzyme also oxidizes the aromatic rings of mono- and dinitrotoluenes at the nitro-substituted carbon, but the basis for this specificity is not understood.
View Article and Find Full Text PDFJ Ind Microbiol Biotechnol
October 2005
Section of Microbiology, University of California, Davis, CA95616, USA.
Acidovorax (formerly Pseudomonas) sp. strain JS42 utilizes 2-nitrotoluene as sole carbon, nitrogen, and energy source. 2-Nitrotoluene 2,3-dioxygenase (2NTDO) catalyzes the initial step in 2-nitrotoluene degradation by converting 2-nitrotoluene to 3-methylcatechol.
View Article and Find Full Text PDF