厌氧氨氧化菌火山口结构

Crateriform structure of anaerobic ammonium-oxidizing bacteria

摘要:

厌氧氨氧化(anaerobic ammonium oxidation,anammox)是微生物学、地质学和环境学领域的重要反应，厌氧氨氧化菌(anaerobic ammonium-oxidizing bacteria,AnAOB)是厌氧氨氧化的驱动器，探明AnAOB的生物学性状对厌氧氨氧化的应用具有重要意义。火山口结构是AnAOB的标志性微观结构，也是AnAOB的重要识别特征。由于迄今没有获得AnAOB纯培养物，相关研究进展缓慢。本文对AnAOB及其所归属的浮霉状菌的火山口结构研究进展作了综述，探讨了火山口结构的形态特征、生理功能和生态意义，得出以下结论：(1)AnAOB的火山口结构均匀分布在细胞表面，其直径约5nm；(2)AnAOB的火山口结构推测向外可连通细胞外膜和内膜，向内可与厌氧氨氧化体膜相连，对于物质转运及转化具有重要意义；(3)火山口结构具有遗传稳定性，其形成可能与鞭毛脱落相关；(4)AnAOB的火山口结构可能通过促进细胞物质交流、信息通讯等在维持其生态位稳定方面起作用。

Abstract:

Anaerobic ammonium oxidation (anammox) is an important reaction in microbiology, geology, and environmental science, and anaerobic ammonium-oxidizing bacteria (AnAOB) are usually regarded as the driver of anammox. Demonstrating the biological characteristics of AnAOB is a vital issue for the application of anammox. Crateriform structure is a special microstructure and has been identified as one of the key features of AnAOB. However, little is known about the crateriform structure of AnAOB due to the failure to isolate AnAOB. In this study, the research advances about the crateriform structure of AnAOB and Planctomycetes were reviewed in terms of morphological characteristics, physiological functions, and ecological effects. Conclusions can be drawn as follows: (1) The crateriform structure of AnAOB is uniformly distributed over the cell surface, with a diameter of about 5 nm. (2) The crateriform structure of AnAOB may connect cytoplasmic membrane, outer membrane, and anammoxosome membrane, and play a role in substrate transport. (3) The crateriform structure has genetic stability, and its formation may be related to flagellum degeneration. (4) The crateriform structure may serve to maintain the niche stability of AnAOB by promoting material exchange and communication between microorganisms.