Characterization and diversity of magnetotactic bacteria from sediments of Caroline Seamount in the Western Pacific Ocean  

作　　者：Kaixuan CUI Wenyan ZHANG Jia LIU Cong XU Yicong ZHAO Si CHEN Hongmiao PAN Tian XIAO Long-Fei WU 

机构地区：[1]CAS Key Laboratory of Marine Ecology and Environmental Sciences,Institute of Oceanology,Chinese Academy of Sciences,Qingdao 266071,China [2]Laboratory for Marine Ecology and Environmental Science,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China [3]University of Chinese Academy of Sciences,Beijing 100049,China [4]Center for Ocean Mega-Science,Chinese Academy of Sciences,Qingdao 266071,China [5]International Associated Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms(LIA-MagMC),CNRS-CAS,Qingdao 266071,China [6]Aix Marseille Univ,CNRS,LCB,IM2B,IMM,Marseille 13009,France [7]National Oceanographic Center,Qingdao 266071,China

出　　处：《Journal of Oceanology and Limnology》2021年第6期2027-2043,共17页海洋湖沼学报（英文）

基　　金：Supported by the National Natural Science Foundation of China(Nos.41776130,41776131);the National Natural Science Foundation of China,Shandong Joint Fund(No.U1706208);the Youth Talent Support Program of the Laboratory for Marine Ecology and Environmental Science,Pilot National Laboratory for Marine Science and Technology(Qingdao)(No.LMEES-YTSP-2018-01-07);the Science&Technology Basic Resources Investigation Program of China(No.2017FY100803)。

摘　　要：Magnetotactic bacteria(MTB)are a group of microorganisms capable of orientating and swimming along magnetic fields because they contain intracellular biomineralized magnetosomes composed of magnetite(Fe 3 O 4)or/and greigite(Fe_(3)S_(4)).They are ubiquitous in freshwater,brackish,and marine habitats,and are cosmopolitan in distribution.However,knowledge of their occurrence and distribution in seamount ecosystems is limited.We investigated the diversity and distribution of MTB in the Caroline Seamount(CM4).The abundance of living MTB in 12 stations in depth varying from 90 to 1545 m was 1.1×10^(3)-43.7×10^(3) inds./dm 3.Despite diverse shapes of MTB observed,magnetotactic cocci were the dominant morphotype and could be categorized into two types:1)typical cocci that appeared to have peritrichous fl agella;and 2)those characterized by having a drop-shaped form and one bundle of fl agella located at the thin/narrow end of the cell.Transmission electron microscopy(TEM)analysis revealed that the magnetosomes formed by those magnetotactic cocci are magnetite(Fe 3 O 4)with octahedral crystal habit.A total of 41 operational taxonomic units(OTUs)of putative MTB(2702 reads)were acquired from nine stations,based on high-throughput sequencing.Of these,40 OTUs belonged to the Proteobacteria phylum and one belonged to the Nitrospirae phylum.We found apparent connectivity between the MTB populations on the Caroline and Kexue(Science in Chinese)seamounts,although the diversity of MTB on Caroline was much richer than on the Kexue Seamount.Our results imply that the unique topography of seamounts and other as-yet unclear environmental factors could lead to evolution of different fl agella arrangements in magnetotactic cocci,and the occurrence of octahedral magnetite magnetosomes.

关 键 词：magnetotactic bacteria Caroline Seamount ABUNDANCE DIVERSITY MAGNETOSOME 

分 类 号：Q938[生物学—微生物学]