Bhushan B, Halasz A, Hawari J
Biotechnology Research Institute, National Research Council of Canada, Montreal, Quebec, Canada.
J Appl Microbiol. 2006 Mar;100(3):555-63. doi: 10.1111/j.1365-2672.2005.02819.x.
To determine the biodegradation of cyclic nitramines by an anaerobic marine bacterium, Clostridium sp. EDB2, in the presence of Fe(III), humic acids (HA) and anthraquinone-2,6-disulfonate (AQDS).
An obligate anaerobic bacterium, Clostridium sp. EDB2, degraded RDX and HMX, and produced similar product distribution including nitrite, methylenedinitramine, nitrous oxide, ammonium, formaldehyde, formic acid and carbon dioxide. Carbon (C) and nitrogen (N) mass balance for RDX products were 87% and 82%, respectively, and for HMX were 88% and 74%, respectively. Bacterial growth and biodegradation of RDX and HMX were stimulated in the presence of Fe(III), HA and AQDS suggesting that strain EDB2 utilized Fe(III), HA and AQDS as redox mediators to transfer electrons to cyclic nitramines.
Strain EDB2 demonstrated a multidimensional approach to degrade RDX and HMX: first, direct degradation of the chemicals; second, indirect degradation by reducing Fe(III) to produce reactive-Fe(II); third, indirect degradation by reducing HA and AQDS which act as electron shuttles to transfer electrons to the cyclic nitramines.
The present study could be helpful in determining the fate of cyclic nitramine energetic chemicals in the environments rich in Fe(III) and HA.
确定厌氧海洋细菌梭菌属EDB2在存在Fe(III)、腐殖酸（HA）和蒽醌-2,6-二磺酸盐（AQDS）的情况下对环状硝胺的生物降解情况。
专性厌氧菌梭菌属EDB2降解了RDX和HMX，并产生了相似的产物分布，包括亚硝酸盐、亚甲基二硝胺、一氧化二氮、铵、甲醛、甲酸和二氧化碳。RDX产物的碳（C）和氮（N）质量平衡分别为87%和82%，HMX的分别为88%和74%。在存在Fe(III)、HA和AQDS的情况下，RDX和HMX的细菌生长及生物降解受到刺激，这表明EDB2菌株利用Fe(III)、HA和AQDS作为氧化还原介质将电子转移至环状硝胺。
EDB2菌株展示了一种多维方法来降解RDX和HMX：首先，直接降解化学物质；其次，通过将Fe(III)还原产生活性Fe(II)进行间接降解；第三，通过还原作为电子穿梭体的HA和AQDS进行间接降解，从而将电子转移至环状硝胺。
本研究有助于确定环状硝胺高能化学品在富含Fe(III)和HA的环境中的归宿。
