摘要
亚硝酸盐氧化细菌(Nitrite Oxidizing Bacteria,NOB)是全球氮循环过程中的关键微生物,主要功能是将亚硝酸盐氧化为硝酸盐。近十年来基于现代分子生态技术的发展,NOB的研究取得了很大的进展,主要包括:NOB的碳氮代谢途径及多样性远远超过以往的认知,如NOB不仅可以氧化亚硝酸盐,也可以氧化尿素、氨以及氰酸盐获取能量;丰富了NOB与环境因素的响应及生态位分化特征的研究,其中Nitrospira更偏好于低氧的贫营养环境,中温的富营养环境更有利于Nitrobacter的生存;对NOB Nitrospira与全程氨氧化细菌(Complete Ammonia Oxidizer,comammox Nitrospira)之间的联系与差异进行了初步探索,二者虽然同属于Nitrospira谱系并且都具备亚硝酸盐氧化能力,但comammox Nitrospira对亚硝酸盐的亲和力较低而对氨具有较高的亲和力,主要分布在低氨的寡营养生境,而NOB Nitrospira对亚硝酸盐有较高亲和力,主要分布在低亚硝酸盐环境。本文基于上述最新研究进展进行了介绍与总结,并对该领域今后的研究进行了展望:在今后的研究中土壤环境或许可以成为NOB研究的新切入点;迫切需要探究缩短NOB分离和培养的方法并结合分子生态技术揭示NOB代谢多样性的实际依据以及NOB在碳氮循环中的真正贡献;探究NOB在代谢和生物化学方面的新机制,为揭示和预测NOB在环境中的响应提供理论支持。
Nitrite-oxidizing bacteria(NOB)play a pivotal role in the global nitrogen cycle by facilitating the conversion of nitrite(NO-2)to nitrate(NO-3).Over the past decade,research on NOB has made great progress,primarily driven by the advancements in microbial and molecular technologies.Recent achievements include:the metabolism versatility and diversity of NOB are far more complicated than what we understood previously.For example,NOB can not only oxidize nitrite but also oxidize urea,ammonia,and cyanate as energy substrates.This finding significantly advanced our comprehension of the response of NOB to environment changes and their ecological niche differentiation,in which Nitrospira species prefer low oxygen,oligotrophic environments,and mesophilic,eutrophic environments are more conducive to the survival of Nitrobacter.The relationship and distinctions between Nitrospira-like NOB and complete ammonia oxidizers(comammox Nitrospira)were analyzed,although both belong to the same Nitrospira lineage and possess nitrite-oxidizing capacity.comammox Nitrospira shows a lower affinity for nitrite but higher affinity for ammonia,and is mainly found in oligotrophic habitats with low ammonia concentration,whereas NOB Nitrospira has a high affinity for nitrite and prefers low-nitrite environments.This paper presents an introductory overview and future prospects for NOB research:soil can be a new entry point for NOB research;more approaches to shorten NOB isolation and culture are needed to reveal the practical basis for the metabolic diversity of NOB as well as the real contribution of NOB to carbon and nitrogen cycling;and new mechanisms in the metabolism and biochemistry of NOB need to be analyzed to reveal and predict the response of NOB to the environment.
作者
胡露星
蒋先军
HU Luxing;JIANG Xianjun(College of Resources and Environment,Southwest University,Chongqing 400715,China)
出处
《农业资源与环境学报》
北大核心
2025年第1期11-21,共11页
Journal of Agricultural Resources and Environment
基金
国家自然科学基金项目(42077035)。
