1. A catabolic pathway for the degradation of chrysene by Pseudoxanthomonas sp. PNK-04
- Author
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Mudde Santosh Kumar, Timmanagouda B. Karegoudar, Sanganal Sanjeev Kumar, Anand S. Nayak, and Oblesha Anjaneya
- Subjects
Chrysene ,Catechol ,Muconic acid ,biology ,Stereochemistry ,biology.organism_classification ,Microbiology ,Citric acid cycle ,chemistry.chemical_compound ,chemistry ,Biochemistry ,Dioxygenase ,Pseudoxanthomonas ,Salicylaldehyde dehydrogenase ,Genetics ,Molecular Biology ,Salicylic acid - Abstract
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.
- Published
- 2011
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