Open AccessA novel pathway for the biodegradation of 3‐nitrotoluene in Pseudomonas putida
Author(s) -
AliSadat Shadan,
Mohan K.S.,
Walia Satish K.
Publication year - 1995
Publication title -
fems microbiology ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.377
H-Index - 155
eISSN - 1574-6941
pISSN - 0168-6496
DOI - 10.1111/j.1574-6941.1995.tb00140.x
Subject(s) - pseudomonas putida , biology , biochemistry , nitrite , metabolite , pseudomonas , biodegradation , dehydrogenase , cofactor , metabolism , strain (injury) , isoprene , enzyme , bacteria , organic chemistry , chemistry , ecology , genetics , anatomy , nitrate , copolymer , polymer
3‐Nitrotoluene was degraded when incubated with the resting cells of Pseudomonas putida OU83. Most of the 3‐nitrotoluene (70%) was metabolized via reduction of the nitro group to form 3‐aminotoluene (3‐AT). A minor portion (30%) was degraded through a novel pathway involving oxidation of 3‐NT to form 3‐nitrophenol through a series of intermediary metabolites: 3‐nitrobenzyl alcohol, 3‐nitrobenzaldehyde and 3‐nitrobenzoic acid. Degradation of 3‐nitrophenol occurred with the formation of a transient intermediary metabolite, hydroxynitroquinone, which was further degraded with the near stoichiometric release of nitrite into the medium. 3‐Nitrotoluene‐induced cells showed increased oxygen consumption with 3‐nitrotoluene, 3‐nitrobenzaldehyde, 3‐nitrobenzoate, and 3‐nitrophenol as substrates in comparison to uninduced cells. Cell extracts prepared from strain OU83 contained benzylalcohol dehydrogenase and benzaldehyde dehydrogenase activities. The experimental evidence suggests a novel pathway for the degradation of 3‐NT in which C‐1 elimination is catalyzed by a cofactor‐independent deformylase, rather than a decarboxylase or dioxygenase.