Biodegradation of 2,4-dinitrotoluene by a Pseudomonas sp

Journal Article · Fri Nov 01 00:00:00 EST 1991 · Applied and Environmental Microbiology; (United States)

OSTI ID:5945087

Spanggord, R J; Mortelmans, K E ^[1]; Spain, J C; Nishino, S F ^[2]

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1. SRI International, Menlo Park, CA (United States)
2. Air Force Engineering and Services Center, Tyndall AFB, FL (United States)

Previous studies of the biodegradation of nonpolar nitroaromatic compounds have suggested that microorganism can reduce the nitro groups but cannot cleave the aromatic ring. The authors report here the initial steps in a pathway for complete biodegradation of 2,4-dinitrotoluene (DNT) by a Pseudomonas sp. isolated from a four-member consortium enriched with DNT. The Pseudomonas sp. degraded DNT as the sole source of carbon and energy under aerobic conditions with stoichiometric release of nitrite. During induction of the enzymes required for growth on DNT, 4-methyl-5-nitrocatechol (MNC) accumulated transiently in the culture fluid when cells grown on acetate were transferred to medium containing DNT as the sole carbon and energy source. Conversion of DNT to MNC in the presence of {sup 18}O{sub 2} revealed the simultaneous incorporation of two atoms of molecular oxygen, which demonstrated that the reaction was catalyzed by a dioxygenase. Fully induced cells degraded MNC rapidly with stoichiometric release of nitrite. The results indicate an initial dioxygenase attack at the 4,5 position of DNT with the concomitant release of nitrite. Subsequent reactions lead to complete biodegradation and removal of the second nitro group as nitrite.

• OSTI ID: 5945087
• Journal Information: Applied and Environmental Microbiology; (United States), Vol. 57:11; ISSN 0099-2240
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
AROMATICS
BIODEGRADATION
NITRO COMPOUNDS
PSEUDOMONAS
METABOLISM
ENZYME ACTIVITY
METABOLITES
NITRITES
OXYGEN 18
OXYGENASES
BACTERIA
CHEMICAL REACTIONS
DECOMPOSITION
ENZYMES
EVEN-EVEN NUCLEI
ISOTOPES
LIGHT NUCLEI
MICROORGANISMS
NITROGEN COMPOUNDS
NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXIDOREDUCTASES
OXYGEN COMPOUNDS
OXYGEN ISOTOPES
PROTEINS
STABLE ISOTOPES
550500* - Metabolism