Chau Anh T T, Lee Matthew, Adrian Lorenz, Manefield Michael J
College of Agriculture and Applied Biology, Cantho University, Can Tho, Vietnam.
School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW, Australia.
Front Microbiol. 2018 Aug 22;9:1927. doi: 10.3389/fmicb.2018.01927. eCollection 2018.
This study investigated syntrophic interactions between chlorinated benzene respiring strain CBDB1 and fermenting partners (, and ) during hexachlorobenzene respiration. Dechlorination rates in syntrophic co-cultures were enhanced 2-3 fold compared to H fed CBDB1 pure cultures (0.23 ± 0.04 μmol Cl day). Syntrophic partners were also able to supply cobalamins to CBDB1, albeit with 3-10 fold lower resultant dechlorination activity compared to cultures receiving exogenous cyanocobalamin. Strain CBDB1 pure cultures accumulated ~1 μmol of carbon monoxide per 87.5 μmol Cl released during hexachlorobenzene respiration resulting in decreases in dechlorination activity. The syntrophic partners investigated were shown to consume carbon monoxide generated by CBDB1, thus relieving carbon monoxide autotoxicity. Accumulation of lesser chlorinated chlorobenzene congeners (1,3- and 1,4-dichlorobenzene and 1,3,5-trichlorobenzene) also inhibited dechlorination activity and their removal from the headspace through adsorption to granular activated carbon was shown to restore activity. Proteomic analysis revealed co-culturing strain CBDB1 with upregulated CBDB1 genes associated with reductive dehalogenases, hydrogenases, formate dehydrogenase, and ribosomal proteins. These data provide insight into CBDB1 ecology and inform strategies for application of CBDB1 in ex situ hexachlorobenzene destruction technologies.
本研究调查了在六氯苯呼吸过程中，氯化苯呼吸菌株CBDB1与发酵伙伴（ 、 和 ）之间的互营相互作用。与以六氯苯为底物的CBDB1纯培养物（0.23±0.04 μmol Cl/天）相比，互营共培养物中的脱氯速率提高了2至3倍。互营伙伴也能够向CBDB1提供钴胺素，尽管与接受外源氰钴胺素的培养物相比，脱氯活性降低了3至10倍。在六氯苯呼吸过程中，CBDB1纯培养物每释放87.5 μmol Cl会积累约1 μmol一氧化碳，导致脱氯活性下降。研究表明，所研究的互营伙伴会消耗CBDB1产生的一氧化碳，从而减轻一氧化碳的自毒性。较少氯化的氯苯同系物（1,3-和1,4-二氯苯以及1,3,5-三氯苯）的积累也会抑制脱氯活性，并且通过吸附到颗粒活性炭上从顶空中去除这些同系物可恢复活性。蛋白质组学分析表明，将菌株CBDB1与 共培养会上调与还原脱卤酶、氢化酶、甲酸脱氢酶和核糖体蛋白相关的CBDB1基因。这些数据为了解CBDB1的生态学提供了见解，并为CBDB1在异位六氯苯销毁技术中的应用策略提供了参考。
