Laboratory of Microbiology, Wageningen University, Wageningen, The Netherlands; NGI Ecogenomics Consortium, Amsterdam, The Netherlands.
Environ Microbiol Rep. 2012 Dec;4(6):604-16. doi: 10.1111/j.1758-2229.2012.00376.x. Epub 2012 Aug 31.
The importance of Dehalobacter species in bioremediation as dedicated degraders of chlorinated organics has been well recognized. However, still little is known about Dehalobacter's full genomic repertoires, including the genes involved in dehalogenation. Here we report the first insights into the genome sequence of Dehalobacter sp. E1 that grows in strict co-culture with Sedimentibacter sp. B4. Based on the co-culture metagenome and the genome of strain B4 (4.2 Mbp) we estimate the genome sequence of strain E1 to be 2.6 Mbp. Ten putative reductive dehalogenase homologue (Rdh)-encoding gene clusters were identified. One cluster has a putative tetrachloroethene Rdh-encoding gene cluster, similar to the pceABCT operon previously identified in Dehalobacter restrictus. Metagenome analysis indicated that the inability of strain E1 to synthesize cobalamin, an essential cofactor of reductive dehalogenases, is complemented by Sedimentibacter. The metagenomic exploration described here maps the extensive dechlorinating potential of Dehalobacter, and paves way for elucidation of the interactions with its co-cultured Sedimentibacter.
作为专门降解氯化有机物的微生物，脱硫杆菌属在生物修复中的重要性已得到广泛认可。然而，人们对脱硫杆菌属的全基因组组成，包括参与脱卤化作用的基因，仍然知之甚少。在这里，我们首次报道了与 Sedimentibacter sp. B4 严格共培养的脱硫杆菌属 E1 的基因组序列。基于共培养宏基因组和菌株 B4（4.2 Mbp）的基因组，我们估计菌株 E1 的基因组序列约为 2.6 Mbp。鉴定出了 10 个可能的还原脱卤酶同源物（Rdh）编码基因簇。其中一个簇具有一个可能的四氯乙烯 Rdh 编码基因簇，类似于先前在 Dehalobacter restrictus 中鉴定的 pceABCT 操纵子。宏基因组分析表明，菌株 E1 不能合成钴胺素，而钴胺素是还原脱卤酶的必需辅因子，Sedimentibacter 可以补充菌株 E1 合成钴胺素的能力。这里描述的宏基因组探索描绘了脱硫杆菌属广泛的脱氯潜力，并为阐明其与共培养的 Sedimentibacter 的相互作用铺平了道路。
