Zhu Baoli, Wang Jiaqi, Bradford Lauren M, Ettwig Katharina, Hu Baolan, Lueders Tillmann
Institute of Groundwater Ecology, Helmholtz Zentrum München, Munich, Germany.
Department of Microbiology, Radboud University Nijmegen, Nijmegen, Netherlands.
Front Microbiol. 2019 Jul 10;10:1577. doi: 10.3389/fmicb.2019.01577. eCollection 2019.
Oxygenic denitrification represents a new route in reductive nitrogen turnover which differs from canonical denitrification in how nitric oxide (NO) is transformed into dinitrogen gas. Instead of NO reduction via NO to N, NO is proposed to be directly disproportionated into N and O in oxygenic denitrification, catalyzed by the putative NO dismutase (Nod). Although a high diversity of genes has been recovered from various environments, still little is known about the niche partitioning and ecophysiology of oxygenic denitrifiers. One constraint is that as a functional marker for oxygenic denitrifiers is not well established. To address this issue, we compared the diversity and phylogeny of , 16S rRNA and gene sequences of four NC10 enrichments that are capable of methane-driven oxygenic denitrification and one environmental sample. The phylogenies of , 16S rRNA and genes of these cultures were generally congruent. The diversity of NC10 bacteria inferred from different genes was also similar in each sample. A new set of NC10-specific primers was developed and used in qPCR. The abundance of NC10 bacteria inferred from genes was constantly lower than via 16S rRNA genes, but the difference was within one order of magnitude. These results suggest that is a suitable molecular marker for studying the diversity and phylogeny of methane-driven oxygenic denitrifiers, the further investigation of which may be of value to develop enhanced strategies for sustainable nitrogen or methane removal.
产氧反硝化作用代表了还原态氮周转的一条新途径，它在一氧化氮（NO）如何转化为氮气方面与经典反硝化作用不同。在产氧反硝化作用中，不是通过将NO还原为N，而是提出由假定的NO歧化酶（Nod）催化，将NO直接歧化为N和O。尽管已经从各种环境中发现了高度多样的基因，但对于产氧反硝化菌的生态位划分和生态生理学仍然知之甚少。一个限制因素是，作为产氧反硝化菌的功能标记尚未得到很好的确立。为了解决这个问题，我们比较了四种能够进行甲烷驱动的产氧反硝化作用的NC10富集培养物以及一个环境样品的、16S rRNA和基因序列的多样性和系统发育。这些培养物的、16S rRNA和基因的系统发育总体上是一致的。从不同基因推断出的NC10细菌的多样性在每个样品中也相似。开发了一组新的NC10特异性引物并用于定量PCR。从基因推断出的NC10细菌的丰度始终低于通过16S rRNA基因推断出的丰度，但差异在一个数量级之内。这些结果表明，是研究甲烷驱动的产氧反硝化菌的多样性和系统发育的合适分子标记，对其进一步研究可能有助于制定可持续去除氮或甲烷的强化策略。
