Hazardous Substance Research Center/South and Southwest, 3221 Patrick Taylor Hall, Baton Rouge, LA 70803, USA.
Chemosphere. 2011 Jun;84(2):247-53. doi: 10.1016/j.chemosphere.2011.04.007. Epub 2011 Apr 30.
Using inoculum from a microcosm study that exhibited aerobic transformation of cis-1,2-dichloroethene (cDCE) and trichloroethene (TCE) commensurate with biodegradation of monoaromatic compounds, enrichment cultures were developed by providing benzene, chlorobenzene (CB), dichlorobenzene (DCB) isomers and 1,2,4-trichlorobenzene as carbon and energy sources. Isolates that grow on benzene, CB, 1,2-DCB and 1,3-DCB were identified as Rhodococcus, Ralstonia, Variovorax and Ralstonia spp., respectively. Cometabolic transformation of cDCE and TCE by resting cells was demonstrated. Transformation capacities (T(c)=0.47-1.0 μg TCE mg(-1)biomass; 1.3-5.3 μg cDCE mg(-1)biomass), transformation yields (T(y)=0.18-0.27 μg TCE mg(-1)substrate; 0.46-2.1 μg cDCE mg(-1)substrate), and pseudo-first-order cometabolic degradation rate constants (0.00081-0.0031 L mg TCE(-1)d(-1); 0.0012-0.030 L mg cDCE(-1)d(-1)) for resting cells grown on benzene, CB, 1,2-DCB and 1,3-DCB were generally lower in comparison to phenol and toluene-grown isolates. Cometabolic transformation of cDCE and TCE also occurred while the cultures concurrently consumed their growth substrate (T(c)(')=0.15-0.33 μg TCE mg(-1)biomass; 4.9-11 μg cDCE mg(-1)biomass; T(y)(')=0.06-0.11 μg TCE mg(-1)substrate; 1.7-4.6 μg cDCE mg(-1)substrate), a condition that is more likely to be encountered in situ compared to cometabolic transformations by resting cells. This study is the first to report transformation rates, capacities, and yields for cometabolism of cDCE and TCE during aerobic growth on benzene, CB, 1,2-DCB and 1,3-DCB. This type of information is needed to predict the potential for natural attenuation when these compounds occur as co-contaminants.
利用表现出与单芳烃化合物生物降解相一致的顺-1,2-二氯乙烯（cDCE）和三氯乙烯（TCE）有氧转化的微宇宙研究接种物，通过提供苯、氯苯（CB）、二氯苯（DCB）异构体和 1,2,4-三氯苯作为碳和能源，开发了富集培养物。在苯、CB、1,2-DCB 和 1,3-DCB 上生长的分离物被鉴定为红球菌、罗尔斯顿菌、鞘氨醇单胞菌和罗尔斯顿菌属。用静止细胞证明了 cDCE 和 TCE 的共代谢转化。转化能力（T(c)=0.47-1.0μg TCE mg(-1)biomass；1.3-5.3μg cDCE mg(-1)biomass）、转化产率（T(y)=0.18-0.27μg TCE mg(-1)substrate；0.46-2.1μg cDCE mg(-1)substrate）和假一级共代谢降解速率常数（0.00081-0.0031L mg TCE(-1)d(-1)；0.0012-0.030L mg cDCE(-1)d(-1)）对于在苯、CB、1,2-DCB 和 1,3-DCB 上生长的静止细胞通常低于苯酚和甲苯生长的分离物。当培养物同时消耗其生长基质时，cDCE 和 TCE 的共代谢转化也会发生（T(c)(')=0.15-0.33μg TCE mg(-1)biomass；4.9-11μg cDCE mg(-1)biomass；T(y)(')=0.06-0.11μg TCE mg(-1)substrate；1.7-4.6μg cDCE mg(-1)substrate），与静止细胞共代谢转化相比，这种情况在现场更有可能发生。本研究首次报道了在苯、CB、1,2-DCB 和 1,3-DCB 有氧生长过程中 cDCE 和 TCE 共代谢的转化速率、能力和产率。当这些化合物作为共污染物出现时，需要这种类型的信息来预测自然衰减的潜力。
