Candidatus Syntrophosphaera thermopropionivorans: a novel player in syntrophic propionate oxidation during anaerobic digestion
Candidatus Syntrophosphaera thermopropionivorans: a novel player in syntrophic propionate oxidation during anaerobic digestion
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DOI：
10.1111/1758-2229.12759
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发表时间：
2019-08-01
影响因子：
3.3
通讯作者：
Gallert, Claudia
中科院分区：
文献类型：
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作者：
Dyksma, Stefan;Gallert, Claudia
丙酸是有机质厌氧矿化的重要中间体。在产甲烷环境中，其降解依赖于合养丙酸氧化细菌(Spob)和古生菌之间的合养联系。然而，到目前为止，只有10个分离的物种被鉴定为Spob。我们报道了共养型丙酸氧化在嗜热假丝酵母菌中的作用，该菌是克隆氏菌亚门的新代表。在增菌培养中，甲烷由丙酸产生，而钙是由丙酸产生的。嗜热丙酸杆菌占细菌总数的63%。CA.的基因组草图。嗜热丙酸杆菌通过甲基丙二酰辅酶A编码丙酸氧化基因。在系统发育上，加州。该菌与未培养的Cloacimonadaceae W5有较近的亲缘关系(16S rRNA基因同源性为86.4%)。革兰氏杆菌。虽然CA.嗜热丙酸菌是从加州嗜热沼气反应器中浓缩而来的。合养磷菌尤其与中温厌氧消化系统有关。16S rRNA基因扩增序列测定和一种新的属特异性定量聚合酶链式反应方法一致地鉴定了钙华。在12个被测试的全规模沼气反应器中，有9个是合养磷杆菌/Cloacimonadaceae W5，因此数量超过了其他Spob，如Pelotomaculum、Smithella和Syntrobacter。总而言之，钙的无处不在和丰富。这些SpoB可能是以前被忽视的合营养性丙酸代谢的关键角色。
Propionate is an important intermediate in the anaerobic mineralization of organic matter. In methanogenic environments, its degradation relies on syntrophic associations between syntrophic propionate-oxidizing bacteria (SPOB) and Archaea. However, only 10 isolated species have been identified as SPOB so far. We report syntrophic propionate oxidation in thermophilic enrichments of Candidatus Syntrophosphaera thermopropionivorans, a novel representative of the candidate phylum Cloacimonetes. In enrichment culture, methane was produced from propionate, while Ca. S. thermopropionivorans contributed 63% to total bacterial cells. The draft genome of Ca. S. thermopropionivorans encodes genes for propionate oxidation via methymalonyl-CoA. Phylogenetically, Ca. S. thermopropionivorans affiliates with the uncultured Cloacimonadaceae W5 and is more distantly related (86.4% 16S rRNA gene identity) to Ca. Cloacimonas acidaminovorans. Although Ca. S. thermopropionivorans was enriched from a thermophilic biogas reactor, Ca. Syntrophosphaera was in particular associated with mesophilic anaerobic digestion systems. 16S rRNA gene amplicon sequencng and a novel genus-specific quantitative PCR assay consistently identified Ca. Syntrophosphaera/Cloacimonadaceae W5 in 9 of 12 tested full-scale biogas reactors thereby outnumbering other SPOB such as Pelotomaculum, Smithella and Syntrophobacter. Taken together the ubiquity and abundance of Ca. Syntrophosphaera, those SPOB might be key players for syntrophic propionate metabolism that have been overlooked before.