0-phthalic acid, a dead-end product in one of the two pathways of phenanthrene degradation in Pseudomonas sp strain PP2
DSpace at IIT Bombay
View Archive InfoField | Value | |
Title |
0-phthalic acid, a dead-end product in one of the two pathways of phenanthrene degradation in Pseudomonas sp strain PP2
|
|
Creator |
KRISHNAN, S
PRABHU, Y PHALE, PS |
|
Subject |
putida ous82
gene-cluster kp7 biodegradation dioxygenase metabolism 1-hydroxy-2-naphthoate dehydrogenase naphthalene pseudomonas sp strain pp2 phenanthrene metabolism 1, 2-dihydroxy naphthalene 0-phthalic acid 1-hydroxy-2-naphthoic acid dioxygenase |
|
Description |
Phenanthrene is degraded via either o-phthalic acid or 1, 2-dihydroxynaphthalene in bacteria. A soil isolate Pseudomonas sp. strain PP2 degrades phenanthrene as the sole source of carbon, but failed to utilize naphthalene [Prabhu and Phale (2003) Appl Microbiol Biotechnol 61:342-351]. Analysis of the phenanthrene-grown culture spent media of this strain by gas chromatography-mass spectrometry (GC-MS) showed accumulation of o-phthalic acid. The cell-free extract prepared from this strain showed activity of 1-hydroxy-2-naphthoic acid dioxygenase (1-H-2-NADO). The extract showed conversion of 1-hydroxy-2-naphthoic acid and 2-carboxybenzaldehyde to o-phthalic acid, as analyzed by thin layer chromatography and GC-MS. However, it failed to grow or respire on o-phthalic acid. These results suggest that besides 1, 2-dihydroxynaphthalene pathway, the strain has a truncated o-phthalic acid pathway for phenanthrene metabolism and excretes o-phthalic acid as a dead-end product, indicating the co-existence of two pathways. 1-H-2-NADO, the key enzyme of o-phthalic acid pathway is inducible, has pH optima of 7.5, does not require external addition of Fe(II) as a co-factor and is completely inhibited by 1,10-phenanthroline. Absence of product formation under anaerobic condition and stoichiometric consumption of 0.82 moles Of O-2 per mole of product formed confirmed the dioxygenase nature of the enzyme.
|
|
Publisher |
NATL INST SCIENCE COMMUNICATION
|
|
Date |
2011-08-19T02:50:28Z
2011-12-26T12:56:01Z 2011-12-27T05:44:02Z 2011-08-19T02:50:28Z 2011-12-26T12:56:01Z 2011-12-27T05:44:02Z 2004 |
|
Type |
Article
|
|
Identifier |
INDIAN JOURNAL OF BIOCHEMISTRY & BIOPHYSICS, 41(5), 227-232
0301-1208 http://dspace.library.iitb.ac.in/xmlui/handle/10054/10200 http://hdl.handle.net/10054/10200 |
|
Language |
en
|
|