AEM
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
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 HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Spain, J. C.
Right arrow Articles by Gibson, D. T.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Spain, J. C.
Right arrow Articles by Gibson, D. T.
Agricola
Right arrow Articles by Spain, J. C.
Right arrow Articles by Gibson, D. T.

 Previous Article  |  Next Article 

Appl Environ Microbiol. 1991 March; 57(3): 812-819
Copyright © 1991, American Society for Microbiology. All Rights Reserved.

Pathway for Biodegradation of p-Nitrophenol in a Moraxella sp

Jim C. Spain* and David T. Gibson

1 Air Force Engineering and Services Center, Tyndall Air Force Base, Florida 32403-6001, and Department of Microbiology and Biocatalysis Research Group, University of Iowa, Iowa City, Iowa 522422

ABSTRACT

A Moraxella strain grew on p-nitrophenol with stoichiometric release of nitrite. During induction of the enzymes for growth on p-nitrophenol, traces of hydroquinone accumulated in the medium. In the presence of 2,2'-dipyridyl, p-nitrophenol was converted stoichiometrically to hydroquinone. Particulate enzymes catalyzed the conversion of p-nitrophenol to hydroquinone in the presence of NADPH and oxygen. Soluble enzymes catalyzed the conversion of hydroquinone to {gamma}-hydroxymuconic semialdehyde, which was identified by high-performance liquid chromatography (HPLC)-mass spectroscopy. Upon addition of catalytic amounts of NAD+, {gamma}-hydroxymuconic semialdehyde was converted to ß-ketoadipic acid. In the presence of pyruvate and lactic dehydrogenase, substrate amounts of NAD were required and {gamma}-hydroxymuconic semialdehyde was converted to maleylacetic acid, which was identified by HPLC-mass spectroscopy. Similar results were obtained when the reaction was carried out in the presence of potassium ferricyanide. Extracts prepared from p-nitrophenol-growth cells also contained an enzyme that catalyzed the oxidation of 1,2,4-benzenetriol to maleylacetic acid. The enzyme responsible for the oxidation of 1,2,4-benzenetriol was separated from the enzyme responsible for hydroquinone oxidation by DEAE-cellulose chromatography. The results indicate that the pathway for biodegradation of p-nitrophenol involves the initial removal of the nitro group as nitrite and formation of hydroquinone. 1,4-Benzoquinone, a likely intermediate in the initial reaction, was not detected. Hydroquinone is converted to ß-ketoadipic acid via {gamma}-hydroxymuconic semialdehyde and maleylacetic acid.

FOOTNOTES

* Corresponding author.

Appl Environ Microbiol. 1991 March; 57(3): 812-819
Copyright © 1991, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. Microbiol. Mol. Biol. Rev. Eukaryot. Cell All ASM Journals

Copyright © 1991 by the American Society for Microbiology. All rights reserved.