锰氧化细菌的生理生态功能与作用机制研究进展

Advances in physiological and ecological functions of manganese oxidizing bacteria and the underlying molecular mechanisms

锰的生物地球化学循环过程与全球尺度的营养元素循环紧密联系,是影响全球生态平衡及气候变化的重要因素之一。在自然界中,锰元素主要以氧化锰和含氧酸盐的矿物形式存在,近年来的研究观点普遍认为细菌介导的氧化作用是自然环境中锰氧化物形成的主要原因。锰氧化细菌广泛分布于海洋、锰矿土壤等生态系统,近期在植物微生态系统中也被发现,其生理生态功能未知。细菌的锰氧化过程是一个复杂的过程,多铜氧化酶和过氧化物(氢)酶是参与该过程的主要酶类,但关于其催化机制的认识尚不成熟。本综述系统探讨锰氧化细菌的种类和分布、细菌锰氧化作用的生理生态功能、参与细菌锰氧化作用的功能酶及其分子机制,总结这一研究领域所取得的成果和仍未解决的科学问题,并对今后的发展方向进行展望。

Coupled with nutrient cycling, the biogeochemical cycling of manganese(Mn) has so far been considered as one of the most important contributors to worldwide ecology balance and environmental changes. In nature, the formation of manganese oxides is driven by bacterial oxidation. Manganese oxidizing bacteria live in various ecosystems including marine and soil systems, and recently, they have been discovered in plant micro-ecosystem with an unknown physiological and ecological function. The bacterial-mediated oxidation of manganese is a complex process in which multicopper oxidase, peroxidase and catalase are the main enzymes involved. However, the action mode of the enzymes are not fully studied. Here, we review the achievements and unresolved problems on biological diversity, physiological and ecological functions of manganese oxidizing bacteria, as well as action mode to in bacterial manganese oxidation. The development trend in this research field is also prospected.