Cosubstrate independent mineralization of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by a Desulfovibrio species under anaerobic conditions

Arnett, Clint M.; Adrian, Neal R.

doi:10.1007/s10532-008-9195-1

Cited by 30 publications

(8 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…RDX can be biodegraded by a range of both anaerobic (Adrian and Sutherland 1999;Arnett and Adrian 2009;Fuller et al 2009;Hawari et al 2001;Zhang and Hughes 2003;Zhao et al 2004) and aerobic bacteria (Bernstein et al 2011;Fournier et al 2002;Fuller et al 2010a;Seth-Smith et al 2002;Thompson et al 2005). In situ anaerobic bioremediation of RDX (and other explosives) has been demonstrated at several sites (Hatzinger and Lippincott 2012;Michalsen et al 2013;Newell 2008;Wade et al 2010).…”

Section: Introductionmentioning

confidence: 99%

Laboratory evaluation of bioaugmentation for aerobic treatment of RDX in groundwater

et al. 2014

View full text Add to dashboard Cite

The potential for bioaugmentation with aerobic explosive degrading bacteria to remediate hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) contaminated aquifers was demonstrated. Repacked aquifer sediment columns were used to examine the transport and RDX degradation capacity of the known RDX degrading bacterial strains Gordonia sp. KTR9 (modified with a kanamycin resistance gene) Pseudomonas fluorescens I-C, and a kanamycin resistant transconjugate Rhodococcus jostii RHA1 pGKT2:Km+. All three strains were transported through the columns and eluted ahead of the conservative bromide tracer, although the total breakthrough varied by strain. The introduced cells responded to biostimulation with fructose (18 mg L(-1), 0.1 mM) by degrading dissolved RDX (0.5 mg L(-1), 2.3 µM). The strains retained RDX-degrading activity for at least 6 months following periods of starvation when no fructose was supplied to the column. Post-experiment analysis of the soil indicated that the residual cells were distributed along the length of the column. When the strains were grown to densities relevant for field-scale application, the cells remained viable and able to degrade RDX for at least 3 months when stored at 4 °C. These results indicate that bioaugmentation may be a viable option for treating RDX in large dilute aerobic plumes.

show abstract

Section: Introductionmentioning

confidence: 99%

Laboratory evaluation of bioaugmentation for aerobic treatment of RDX in groundwater

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Aerobic degradation proceeds via two single-electron transfer steps resulting in sequential denitration (2 NO 2 Ϫ removed) followed by ring cleavage and production of 4-nitro-2,4-diazabutanal (NDAB) (pathway C) (7). Some bacteria are able to utilize RDX as a nitrogen source (13)(14)(15), and at least one sulfate-reducing culture that is able to utilize RDX as a sole source of carbon, nitrogen, and energy has been isolated (16).…”

mentioning

confidence: 99%

Relating Carbon and Nitrogen Isotope Effects to Reaction Mechanisms during Aerobic or Anaerobic Degradation of RDX (Hexahydro-1,3,5-Trinitro-1,3,5-Triazine) by Pure Bacterial Cultures

Fuller

Heraty

Condee

et al. 2016

Appl Environ Microbiol

View full text Add to dashboard Cite

Kinetic isotopic fractionation of carbon and nitrogen during RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) biodegradation was investigated with pure bacterial cultures under aerobic and anaerobic conditions. Relatively large bulk enrichments in 15 ؊ production were much larger than, but systematically related to, the bulk RDX N isotope effects with different bacteria. Apparent intrinsic 15 N-NO 2 ؊ values were consistent with an initial denitration pathway in the aerobic experiments and more complex processes of NO 2 ؊ formation associated with anaerobic ring cleavage. These results indicate the potential for isotopic analysis of residual RDX for the differentiation of degradation pathways and indicate that further efforts to examine the isotopic composition of potential RDX degradation products (e.g., NO x ) in the environment are warranted. IMPORTANCEThis work provides the first systematic evaluation of the isotopic fractionation of carbon and nitrogen in the organic explosive RDX during degradation by different pathways. It also provides data on the isotopic effects observed in the nitrite produced during RDX biodegradation. Both of these results could lead to better understanding of the fate of RDX in the environment and help improve monitoring and remediation technologies. Explosives manufacturing, testing, and training range activities have resulted in the release of explosive compounds, including the nitramine explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), in soils at numerous U.S. Department of Defense (DoD) installations. Because RDX is mobile in soils and persistent, it has also been detected in groundwater or drinking water at some of these sites (1, 2).There has been extensive research examining the biological degradation of explosive compounds by pure cultures of bacteria as well as mixed consortia (for a review, see reference 3). RDX biodegradation has been observed under a range of redox conditions (4-9), and at least three predominant degradation pathways have been elucidated (Fig. 1). Typically, RDX is degraded anaerobically as an electron acceptor, requiring a carbon source as an electron donor, and entails either successive reduction of the three nitro groups via successive two-electron (2e Ϫ ) transfers followed by ring cleavage (pathway A) or an earlier opening of the ring structure (pathway B1), with or without initial denitration (pathway B2). The specific mechanism of ring destabilization and the steps that lead to ring cleavage may be variable and remain subject to debate (6,7,10). A denitration reaction that converts hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) (in pathway A) through multiple intermediates to methylenedinitramine (MEDINA) (in pathway B) under anaerobic conditions has also been proposed (7,11,12). Aerobic degradation proceeds via two single-electron transfer steps resulting in sequential denitration (2 NO 2 Ϫ removed) followed by ring cleavage and production of 4-nitro-2,4-diazabutanal (NDAB) (pathway C) (7). Some bacteria are able to utilize R...

show abstract

“…It could further be concluded that RDX is capable acting as electron acceptor as well as electron donor in the absence of suitable exogenous donors. A previous study also showed that a sulfate‐reducing bacterium could degrade RDX in 63 days when incubated with RDX as sole carbon source 21…”

Section: Resultsmentioning

confidence: 91%

Degradation of hexahydro‐1,3,5‐trinitro‐1,3, 5‐triazine (RDX) by anaerobic mesophilic granular sludge from a UASB reactor

Huang

et al. 2010

J of Chemical Tech & Biotech

View full text Add to dashboard Cite

BACKGROUND: This study investigated the performance of anaerobic mesophilic granular sludge for the degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Batch tests were conducted to investigate the effects of different supplements on the RDX degradation ability of anaerobic granular sludge, as well as the contributions of both physicochemical and biological processes involved in RDX removal from aqueous solution.

show abstract

Cosubstrate independent mineralization of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by a Desulfovibrio species under anaerobic conditions

Cited by 30 publications

References 34 publications

Laboratory evaluation of bioaugmentation for aerobic treatment of RDX in groundwater

Laboratory evaluation of bioaugmentation for aerobic treatment of RDX in groundwater

Relating Carbon and Nitrogen Isotope Effects to Reaction Mechanisms during Aerobic or Anaerobic Degradation of RDX (Hexahydro-1,3,5-Trinitro-1,3,5-Triazine) by Pure Bacterial Cultures

Degradation of hexahydro‐1,3,5‐trinitro‐1,3, 5‐triazine (RDX) by anaerobic mesophilic granular sludge from a UASB reactor

Contact Info

Product

Resources

About