摘要
厌氧氨氧化(Anammox)是以铵为电子供体将亚硝酸盐转化为氮气的生物过程。厌氧氨氧化菌(AAOB)生理代谢和细胞结构均十分特殊,且在氮素循环中起着十分重要的作用。厌氧氨氧化已成为环境学、微生物学、海洋学等领域的研究热点。但是,至今人们未能对厌氧氨氧化菌进行纯培养,这严重限制了对厌氧氨氧化菌的深入研究。群体感应是一种普遍存在于微生物细胞之间的通讯机制,它具有根据菌群密度和周围环境变化调节基因表达,以控制细菌群体行为的功能。厌氧氨氧化菌活性的细胞密度效应和生物团聚行为与细菌中普遍存在的群体感应现象相符。探讨了厌氧氨氧化菌群体感应系统存在的可能性、工作机制及其生态学意义,以期为厌氧氨氧化菌的分离培养、团聚体培育等提供理论指导。
Anaerobic ammonium oxidation（Anammox）is a unique anaerobic biological reaction which converts ammonium and nitrite into nitrogen gas and plays an important role in the nitrogen biogeochemical cycle.It is now estimated that Anammox might contribute more than 50% to global present day nitrogen losses from the ocean.Anaerobic ammonium-oxidizing bacteria（AAOB） as the responsible chemolithoautotrophic bacteria are grouped into the phylum Planctomycetes.Now a family of Anammoxaceae including five genera,ten species of AAOB are established.AAOB have some distinct characters in the physiology,metabolism and cell structure.AAOB are chemoautotrophic bacteria which use carbon dioxide or bicarbonate as the main carbon source and ammonium or nitrite as the energy source.AAOB produce hydrazine or hydroxylamine as the very unusual intermediates.AAOB have a particular cell wall structure,cell membrane component and inner cell structure.Currently Anammox are one of hot-spots in the fields of environmental science,microbiology and marine science.So far,however,AAOB have not been isolated and cultivated in pure culture,which has become a great obstacle in the related studies.Besides,applications of Anammox process are also limited without making AAOB′s characters clear.Quorum sensing may provide us another perspective to understand AAOB.Quorum-sensing is a common signal sensing mechanism by which bacteria monitor their population density.Quorum sensing system allows bacteria to regulate their gene expression according to the population density and the environmental condition so as to alter their behavior on a population scale.The ability of rapidly altering gene expression and consequently behavior in response to a dynamic environment give bacteria the plasticity to survive in rich,neutural and hostile condition.Bacteria communicate with one another using chemical signal molecules termed autoinducers.In quorum-sensing bacteria,chemical communication involves producing,releasing,detecting,and responding to small hormone-li
出处
《生态学报》
CAS
CSCD
北大核心
2012年第8期2581-2587,共7页
Acta Ecologica Sinica
基金
国家863项目(2009ZZ06311)
国家自然科学基金(31070110)
浙江省自然科学基金重点项目(Z5110094)
关键词
厌氧氨氧化菌
群体感应
自诱导物
工作机制
竞争
anaerobic ammonium oxidation bacteria
quorum sensing
autoinducer
working mechanism
competition
