Biodegradation of phenanthrene by Pseudomonas sp. strain PPD: purification and characterization of 1-hydroxy-2-naphthoic acid dioxygenase

There are no files associated with this record.

Title Biodegradation of phenanthrene by Pseudomonas sp. strain PPD: purification and characterization of 1-hydroxy-2-naphthoic acid dioxygenase
Author Deveryshetty, Jaigeeth; Phale, Prashant S.
Journal Name Microbiology
Editor H L Drake
Year Published 2009
Place of publication United Kingdom
Publisher Society for General Microbiology
Abstract Pseudomonas sp. strain PPD can metabolize phenanthrene as the sole source of carbon and energy via the 'phthalic acid' route. The key enzyme, 1-hydroxy-2-naphthoic acid dioxygenase (1-HNDO, EC 1.13.11.38), was purified to homogeneity using a 3-hydroxy-2-naphthoic acid (3-H2NA)-affinity matrix. The enzyme was a homotetramer with a native molecular mass of 160 kDa and subunit molecular mass of ∼39 kDa. It required Fe(II) as the cofactor and was specific for 1-hydroxy-2-naphthoic acid (1-H2NA), with Km 13.5 μM and Vmax 114 μmol min−1 mg−1. 1-HNDO failed to show activity with gentisic acid, salicylic acid and other hydroxynaphthoic acids tested. Interestingly, the enzyme showed substrate inhibition with a Ki of 116 μM. 1-HNDO was found to be competitively inhibited by 3-H2NA with a Ki of 24 μM. Based on the pH-dependent spectral changes, the enzyme reaction product was identified as 2-carboxybenzalpyruvic acid. Under anaerobic conditions, the enzyme failed to convert 1-H2NA to 2-carboxybenzalpyruvic acid. Stoichiometric studies showed the incorporation of 1 mol O2 into the substrate to yield 1 mol product. These results suggest that 1-HNDO from Pseudomonas sp. strain PPD is an extradiol-type ring-cleaving dioxygenase.
Peer Reviewed Yes
Published Yes
Alternative URI http://dx.doi.org/10.1099/mic.0.030460-0
Volume 155
Issue Number 9
Page from 3083
Page to 3091
ISSN 1465-2080
Date Accessioned 2011-03-28
Language en_AU
Faculty Faculty of Science, Environment, Engineering and Technology
Subject Structural Biology (incl Macromolecular Modelling)
URI http://hdl.handle.net/10072/39184
Publication Type Journal Articles (Refereed Article)
Publication Type Code c1x

Show simple item record

Griffith University copyright notice