产甲烷菌
产甲烷
生物
古细菌
广域古菌界
克雷纳恰奥塔
念珠菌
生物化学
遗传学
基因组
细菌
基因
作者
Masaru K. Nobu,Takashi Narihiro,Kyohei Kuroda,Renwei Mei,Wen Tso Liu
出处
期刊:The ISME Journal
[Springer Nature]
日期:2016-03-04
卷期号:10 (10): 2478-2487
被引量:236
标识
DOI:10.1038/ismej.2016.33
摘要
The ecophysiology of one candidate methanogen class WSA2 (or Arc I) remains largely uncharacterized, despite the long history of research on Euryarchaeota methanogenesis. To expand our understanding of methanogen diversity and evolution, we metagenomically recover eight draft genomes for four WSA2 populations. Taxonomic analyses indicate that WSA2 is a distinct class from other Euryarchaeota. None of genomes harbor pathways for CO2-reducing and aceticlastic methanogenesis, but all possess H2 and CO oxidation and energy conservation through H2-oxidizing electron confurcation and internal H2 cycling. As the only discernible methanogenic outlet, they consistently encode a methylated thiol coenzyme M methyltransferase. Although incomplete, all draft genomes point to the proposition that WSA2 is the first discovered methanogen restricted to methanogenesis through methylated thiol reduction. In addition, the genomes lack pathways for carbon fixation, nitrogen fixation and biosynthesis of many amino acids. Acetate, malonate and propionate may serve as carbon sources. Using methylated thiol reduction, WSA2 may not only bridge the carbon and sulfur cycles in eutrophic methanogenic environments, but also potentially compete with CO2-reducing methanogens and even sulfate reducers. These findings reveal a remarkably unique methanogen 'Candidatus Methanofastidiosum methylthiophilus' as the first insight into the sixth class of methanogens 'Candidatus Methanofastidiosa'.
科研通智能强力驱动
Strongly Powered by AbleSci AI