Fraunhofer-Gesellschaft

Publica

Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

A new 4-nitrotoluene degradation pathway in a mycobacterium strain

 

Applied and environmental microbiology 64 (1998), No.2, pp.446-452 : Ill., Lit.
ISSN: 0099-2240
English
Journal Article
Fraunhofer IGB ()
4-nitrotoluene; degradation; HL 4-NT-1; mycrobacterium; sp. strain

Abstract
Mycobacterium sp. strain HL 4-NT-1, isolated from a mixed soil sample from the Stuttgart area, utilized 4-nitrotoluene as the sole source of nitrogen, carbon, and energy. Under aerobic conditions, resting cells of the Mycobacterium strain metabolized 4-nitrotoluene with concomitant release of small amounts of ammonia; under anaerobic conditions, 4-nitrotoluene was completely converted to 6-amino-m-cresol. 4-Hydroxylaminotoluene was converted to 6-amino-m cresol by cell extracts and thus could be confirmed as the initial metabolite in the degradative pathway. This enzymatic equivalent to the acid-catalyzed Bamberger rearrangement requires neither cofactors nor oxygen. In the same crucial enzymatic step, the homologous substrate hydroxylaminobenzene was rearranged to 2-aminophenol. Abiotic oxidative dimerization of 6-amino-m-cresol, observed during growth of the Mycobacterium strain, yielded a yellow dihydrophenoxazinone. Another yellow metabolite (lambda max. 385 nm) was tentatively identified as 2-amino-5-methylmuconic semialdehyde, formed from 6-amino-m-cresol by meta ring cleavage.

: http://publica.fraunhofer.de/documents/PX-26054.html