An abundant bacterial phylum with nitrite-oxidizing potential in oligotrophic marine sediments
An abundant bacterial phylum with nitrite-oxidizing potential in oligotrophic marine sediments
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DOI：
10.1038/s42003-024-06136-2
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发表时间：
2024-04-11
影响因子：
5.9
通讯作者：
Babbin，Andrew R.
中科院分区：
文献类型：
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作者：
Zhao，Rui;Jorgensen，Steffen L.;Babbin，Andrew R.
亚硝酸盐氧化菌（NOB）是重要的硝化菌，其活性调节着生态系统中亚硝酸盐的有效性并决定着氮的损失程度。在含氧海洋沉积物中，氨氧化古菌（AOA）和NOB共同催化氨氧化生成硝酸盐，但部分岩心中AOA与标准NOB的丰度比明显高于实际海洋条件下AOA和NOB生理特性预测的理论丰度范围，表明一些NOB尚未被发现。在这里，我们报告了一种细菌门candidatusnitrosediminicolota，其成员比规范的nob更丰富，并且广泛分布于全球的少营养沉积物中。Nitrosediminicolota成员除了具有尿素水解和硫代硫酸盐还原等其他辅助功能外，还具有氧化亚硝酸盐的功能潜力。虽然一种恢复的物种（Ca. Nitrosediminicola aerophilus）通常局限于缺氧区，但另一种（Ca. Nitrosediminicola厌氧耐受性）也出现在缺氧沉积物中。CountingCa。Nitrosediminicolota作为一种亚硝酸盐氧化剂，有助于解决海洋含氧沉积物中AOA与NOB之间明显的丰度失衡，其活性可能对亚硝酸盐收支起控制作用。
Nitrite-oxidizing bacteria (NOB) are important nitrifiers whose activity regulates the availability of nitrite and dictates the magnitude of nitrogen loss in ecosystems. In oxic marine sediments, ammonia-oxidizing archaea (AOA) and NOB together catalyze the oxidation of ammonium to nitrate, but the abundance ratios of AOA to canonical NOB in some cores are significantly higher than the theoretical ratio range predicted from physiological traits of AOA and NOB characterized under realistic ocean conditions, indicating that some NOBs are yet to be discovered. Here we report a bacterial phylumCandidatusNitrosediminicolota, members of which are more abundant than canonical NOBs and are widespread across global oligotrophic sediments.Ca. Nitrosediminicolota members have the functional potential to oxidize nitrite, in addition to other accessory functions such as urea hydrolysis and thiosulfate reduction. While one recovered species (Ca. Nitrosediminicola aerophilus) is generally confined within the oxic zone, another (Ca. Nitrosediminicola anaerotolerans) additionally appears in anoxic sediments. CountingCa. Nitrosediminicolota as a nitrite-oxidizer helps to resolve the apparent abundance imbalance between AOA and NOB in oxic marine sediments, and thus its activity may exert controls on the nitrite budget.