Open AccessA catabolic pathway for the degradation of chrysene by Pseudoxanthomonas sp. PNK‐04
Author(s) -
Nayak Anand S.,
Sanjeev Kumar Sanganal,
Santosh Kumar Mudde,
Anjaneya Oblesha,
Karegoudar Timmanagouda B.
Publication year - 2011
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.2011.02301.x
Subject(s) - chrysene , catechol , salicylic acid , muconic acid , chemistry , biochemistry , metabolite , catabolism , dioxygenase , metabolism , enzyme , organic chemistry , urine , pyrene
The chrysene‐degrading bacterium Pseudoxanthomonas sp. PNK‐04 was isolated from a coal sample. Three novel metabolites, hydroxyphenanthroic acid, 1‐hydroxy‐2‐naphthoic acid and salicylic acid, were identified by TLC, HPLC and MS. Key enzyme activities, namely 1‐hydroxy‐2‐naphthoate hydroxylase, 1,2‐dihydroxynaphthalene dioxygenase, salicylaldehyde dehydrogenase and catechol‐1,2‐dioxygenase, were noted in the cell‐free extract. These results suggest that chrysene is catabolized via hydroxyphenanthroic acid, 1‐hydroxy‐2‐naphthoic acid, salicylic acid and catechol. The terminal aromatic metabolite, catechol, is then catabolized by catechol‐1,2‐dioxygenase to cis,cis ‐muconic acid, ultimately forming TCA cycle intermediates. Based on these studies, the proposed catabolic pathway for chrysene degradation by strain PNK‐04 is chrysene → hydroxyphenanthroic acid → 1‐hydroxy‐2‐naphthoic acid → 1,2‐dihydroxynaphthalene → salicylic acid → catechol → cis,cis ‐muconic acid.