creators_name: Vikram, Surendra
creators_name: Pandey, Janmejay
creators_name: Bhalla, Nidhi
creators_name: Pandey, Gunjan
creators_name: Ghosh, Anuradha
creators_name: Khan, Fazlurrahman
creators_name: Jain, R K
creators_name: Raghava, G.P.S.
type: article
datestamp: 2013-01-29 06:03:47
lastmod: 2015-01-08 09:22:39
metadata_visibility: show
title: Branching of the p-nitrophenol (PNP) degradation pathway in burkholderia sp. Strain SJ98: Evidences from genetic characterization of PNP gene cluster.
ispublished: pub
subjects: QR
note: his is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. 
abstract: Aerobic microbial degradation of p-nitrophenol (PNP) has been classically shown to proceed via 'Hydroquinone (HQ) pathway' in Gram-negative bacteria, whereas in Gram-positive PNP degraders it proceed via 'Benzenetriol (BT) pathway'. These pathways are characterized by the ring cleavage of HQ and BT as terminal aromatic intermediates respectively. Earlier reports on PNP degradation have indicated these pathways to be mutually exclusive. We report involvement of both 'HQ' and 'BT' ring cleavage pathways in PNP degradation by Burkholderia sp. strain SJ98. Genetic characterization of an ~41 Kb DNA fragment harboring PNP degradation gene cluster cloned and sequenced from strain SJ98 showed presence of multiple orfs including pnpC and pnpD which corresponded to previously characterized 'benzenetriol-dioxygenase (BtD)' and 'maleylacetate reductase (MaR)' respectively. This gene cluster also showed presence of pnpE1 and pnpE2, which shared strong sequence identity to cognate sub-units of 'hydroquinone dioxygenase' (HqD). Heterologous expression and biochemical characterization ascertained the identity of PnpE1 and PnpE2. In in vitro assay reconstituted heterotetrameric complex of PnpE1 and PnpE2 catalyzed transformation of hydroquinone (HQ) into corresponding hydroxymuconic semialdehyde (HMS) in a substrate specific manner. Together, these results clearly establish branching of PNP degradation in strain SJ98. We propose that strain SJ98 presents a useful model system for future studies on evolution of microbial degradation of PNP.
date: 2012
date_type: published
publication: AMB Express
volume: 2
number: 1
publisher: Springer
pagerange: 30
refereed: TRUE
issn: 2191-0855
official_url: http://www.amb-express.com/content/2/1/30
related_url_url: http://www.amb-express.com/content/2/1/30
related_url_type: pub
citation:   Vikram, Surendra and Pandey, Janmejay and Bhalla, Nidhi and Pandey, Gunjan and Ghosh, Anuradha and Khan, Fazlurrahman and Jain, R K and Raghava, G.P.S.  (2012) Branching of the p-nitrophenol (PNP) degradation pathway in burkholderia sp. Strain SJ98: Evidences from genetic characterization of PNP gene cluster.  AMB Express, 2 (1).  p. 30.  ISSN 2191-0855     
document_url: http://crdd.osdd.net/open/1242/1/raghava2012.4.pdf