Degradation of 2,4-dinitroanisole (DNAN) by metabolic cooperative activity of Pseudomonas sp. strain FK357and Rhodococcus imtechensis strain RKJ300.
2,4-Dinitroanisole (DNAN) is an insensitive explosive ingredient used by many defense agencies as a replacement for 2,4,6-trinitrotoluene. Although the biotransformation of DNAN under anaerobic condition has been reported, aerobic microbial degradation pathway has not been elucidated. An n-methyl-4-nitroaniline degrading bacterium Pseudomonas sp. strain FK357 transformed DNAN into 2,4-dinitrophenol (2,4-DNP) as an end product. Interestingly, when strain FK357 was co-cultured with a 2,4-DNP degrading Rhodococcus imtechensis strain RKJ300, complete and high rate of DNAN degradation was observed with no accumulation of intermediates. Enzyme assay using cell extracts of strain FK357 demonstrated that O-demethylation reaction is the first step of DNAN degradation with formation of 2,4-DNP and formaldehyde as intermediates. Subsequently, 2,4-DNP was degraded by strain RKJ300 via the formation of hydride-Meisenheimer complex. The present study clearly demonstrates that complete degradation of DNAN occurs as a result of the metabolic cooperative activity of two members within a bacterial consortium.
Institute of Microbial Technology, Sector 39-A, Chandigarh 160036, India.
Fazlurrahman
F
Khan
Deepika
D
Pal
Anuradha
A
Ghosh
Swaranjit Singh
SS
Cameotra
D000814:Aniline Compounds; D000840:Anisoles / Q000032:analysis / Q000378:metabolism*; D001673:Biodegradation, Environmental; D001711:Biotransformation; D053834:Explosive Agents / Q000032:analysis / Q000378:metabolism; D015386:Hazardous Substances / Q000032:analysis / Q000378:metabolism*; D011549:Pseudomonas / Q000378:metabolism / Q000502:physiology*; D012240:Rhodococcus / Q000378:metabolism / Q000502:physiology*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism*
D000814:Aniline Compounds; D000840:Anisoles; D053834:Explosive Agents; D015386:Hazardous Substances; C554272:N-methyl-4-nitroaniline; D014874:Water Pollutants, Chemical; C539360:2,4-dinitroanisole
2,4-Dinitroanisole (DNAN); 2,4-Dinitrophenol (2,4-DNP); Biodegradation; Co-culture; Hydride-Meisenheimer complex