海洋蓝细菌与异养细菌相互作用:以原绿球藻为例  

Interactions between marine cyanobacteria and heterotrophic bacteria:A case study of Prochlorococcus

作　　者：冯雪金 林大晖 严威 张锐[1] 焦念志[1] Xuejin Feng;Ta-Hui Lin;Wei Yan;Rui Zhang;Nianzhi Jiao(State Key Laboratory of Marine Environmental Science,Fujian Key Laboratory of Marine Carbon Sequestration,College of Ocean and Earth Sciences,Xiamen University,Xiamen 561102,China;College of Marine Science and Technology,China University of Geosciences,Wuhan 430074,China)

机构地区：[1]厦门大学海洋与地球学院,福建省海洋碳汇重点实验室,近海海洋环境科学国家重点实验室,厦门361102 [2]中国地质大学(武汉)海洋学院,武汉430074

出　　处：《科学通报》2021年第30期3839-3848,共10页Chinese Science Bulletin

基　　金：国家自然科学基金组织间国际合作项目(41861144018);国家自然科学基金(41906110);中央高校基本科研业务费(20720170107)资助。

摘　　要：蓝细菌(cyanobacteria)是海洋最主要的初级生产者,贡献了海洋净初级生产力的25%.海洋异养细菌具有多种代谢路径,能够吸收和利用蓝细菌的光合作用产物.海洋蓝细菌和异养细菌之间的相互作用关系影响海洋食物网、固碳和储碳,具有重要的生态效应和生物地球化学意义.原绿球藻(Prochlorococcus)作为蓝细菌的典型代表类群,是海洋中体积最小、数量最大的光合自养原核微生物.原绿球藻的基因组高度精简,从而减少了细胞复制中所需的物质和能量,同时减小了细胞体积,因此在寡营养大洋表层环境中具有竞争优势.然而,基因组减小同时使得原绿球藻单个细胞基因多样性下降,从而使其适应环境的潜能降低.因此,相比于其他蓝细菌,原绿球藻更加依赖于海洋环境中其他微生物的协助,以维持自身生存的需求.本文根据国内外近期的相关研究成果,从原绿球藻与异养细菌之间基因的互补关系和生理特性等角度,归纳了两者之间存在的互利共生、偏利共生等多种相互作用关系及其生态效应,并提出了未来的研究重点.Cyanobacteria are the key primary producers in the global ocean and account for 25%of its net productivity.They play a vital role in the ocean by driving the circulation of matter and the flow of energy via the absorption of considerable amounts of carbon dioxide and the release of dissolved organic matter.This dissolved organic matter is converted into biomass by marine heterotrophs,which keeps the cycling of elements in oligotrophic waters at equilibrium.Prochlorococcus,an ecologically important genus of cyanobacteria,is the smallest and most abundant oxygenic phototroph in the global ocean.Prochlorococcus has highly streamlined genomes,which can provide a competitive advantage in the oligotrophic surface waters;however,the streamlined genomes also force Prochlorococcus to adapt to a narrow range of environmental parameters.Owing to these genomic characteristics,Prochlorococcus often establishes interactions with heterotrophic bacteria to survive in the challenging marine environment.Because cyanobacteria are abundant in the ocean,the cyanobacteria-heterotrophic bacteria relationship can significantly affect marine carbon sequestration and storage,which in turn has important ecological implications.Previous studies have reported on the relationships between Prochlorococcus and various heterotrophic bacteria.For example,Prochlorococcus establishes positive interactions with Alteromonas sp.that enhance its growth rate and environmental adaptability.In this review,we discuss the underlying mechanisms of the interaction patterns between Prochlorococcus and heterotrophic bacteria,as well as their genetic,physiological,and ecological significance.Prochlorococcus and heterotrophic bacteria tend to form mutualistic relationships in which they directly or indirectly exchange metabolites or recycle organic carbon through complementary excretion and crosstalk between pathways,such as citrate,glycolate,and malate pathways.Prochlorococcus and heterotrophic bacteria also commonly establish commensal relationships.For instanc

关 键 词：蓝细菌 原绿球藻 异养细菌 相互作用 互利共生 偏利共生 

分 类 号：Q935[生物学—微生物学]