Mingo Felix S, Studenik Sandra, Diekert Gabriele
Department of Applied and Ecological Microbiology, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany.
FEMS Microbiol Ecol. 2014 Dec;90(3):783-90. doi: 10.1111/1574-6941.12433. Epub 2014 Oct 20.
Microbial growth coupled to O-demethylation of phenyl methyl ethers, which are lignin decomposition products, was described for acetogenic bacteria and recently also for two species belonging to the nonacetogenic genus Desulfitobacterium. To elucidate the potential role of desulfitobacteria in the O-demethylation of phenyl methyl ethers in the environment, we cultivated Desulfitobacterium chlororespirans, D. dehalogenans, D. metallireducens, and different strains of D. hafniense with phenyl methyl ethers as sole electron donors. With the exception of D. metallireducens, all species and strains tested were able to demethylate at least three of the four phenyl methyl ethers applied with fumarate, nitrate, or thiosulfate as electron acceptor. Furthermore, a high number of operons putatively encoding demethylase systems were identified in the genomes of Desulfitobacterium spp., although discrimination between O-, S-, N- and, Cl-demethylases was not possible. These findings provide evidence for the importance of the methylotrophic metabolism for desulfitobacteria and point to their involvement in the O-demethylation of phenyl methyl ethers in the environment.
产乙酸细菌中描述了微生物生长与木质素分解产物苯基甲基醚的O-去甲基化相关联的情况，最近在非产乙酸的脱硫脱硫弧菌属的两个物种中也有相关报道。为了阐明脱硫脱硫弧菌在环境中苯基甲基醚O-去甲基化中的潜在作用，我们以苯基甲基醚作为唯一电子供体，培养了氯呼吸脱硫脱硫弧菌、脱卤脱硫脱硫弧菌、金属还原脱硫脱硫弧菌以及哈夫尼脱硫脱硫弧菌的不同菌株。除了金属还原脱硫脱硫弧菌外，所有测试的物种和菌株都能够以富马酸盐、硝酸盐或硫代硫酸盐作为电子受体，对所应用的四种苯基甲基醚中的至少三种进行去甲基化。此外，在脱硫脱硫弧菌属的基因组中鉴定出了大量推测编码去甲基酶系统的操纵子，尽管无法区分O-、S-、N-和Cl-去甲基酶。这些发现为甲基营养型代谢对脱硫脱硫弧菌的重要性提供了证据，并表明它们参与了环境中苯基甲基醚的O-去甲基化过程。
