Community Composition and Diversity of Coastal Bacterioplankton Assemblages in Lakes Michigan, Erie, and Huron
Community Composition and Diversity of Coastal Bacterioplankton Assemblages in Lakes Michigan, Erie, and Huron
复制标题
密歇根湖、伊利湖和休伦湖沿海浮游细菌群落的群落组成和多样性
作者：
O. Olapade
位于北美东部的劳伦森五大湖，包括苏必利尔湖、密歇根湖、休伦湖、伊利湖和安大略湖，被认为是世界上最大的淡水湖；然而，在这些巨大的淡水系统中，对本地微生物组合的多样性和分布知之甚少。因此，为了描述这些水生环境中的微生物结构和群落组成，利用高通量测序和荧光原位杂交（FISH）方法的组合，定量表征了位于密歇根湖、休伦湖和伊利湖沿岸地区六个不同地点的浮游细菌组合的发生、多样性和分布。系统发育检查显示细菌群落多样，属于11个不同的分类类群。焦氧测序结果显示，大部分序列集中在Proteobacteria、Bacteriodetes、Actinobacteria和Cyanobacteria四个主要类群中，而荧光原位杂交也显示，在6个调查的湖泊遗址中，Gammaproteobacteria和Cytophaga-Flavobacterium的成员数量优势。总体而言，在所调查的湖泊站点中，这些组合显示出相当多样化的分布，主要由各种异养种群组成，除了伊利湖-桑达斯基湾站点外，自养蓝藻占50%以上的优势。这表明水化学和各种人为干扰以及湖泊形态特征等因素的组合可能影响系统内细菌组合的群落结构和多样性。
The Laurentian Great Lakes, including Lakes Superior, Michigan, Huron, Erie, and Ontario, located in the eastern part of North America are considered the largest of freshwater lakes in the world; however, very little is known about the diversity and distribution of indigenous microbial assemblages within these vast bodies of freshwater systems. Therefore, to delineate the microbial structure and community composition in these aquatic environments, combinations of high-throughput sequencing and fluorescent in situ hybridization (FISH) approaches were utilized to quantitatively characterize the occurrence, diversity, and distribution of bacterioplankton assemblages in six different sites located along the coastal regions of Lakes Michigan, Huron, and Erie. Phylogenetic examination showed a diverse bacterial community belonging to 11 different taxonomic groups. Pyrosequencing results revealed that the majority of the sequences were clustered into four main groups, i.e., Proteobacteria, Bacteriodetes, Actinobacteria, and Cyanobacteria, while fluorescent in situ hybridization also showed the numerical dominance of members of the Gammaproteobacteria and the Cytophaga-Flavobacterium in the six lake sites examined. Overall, the assemblages were shown to be quite diverse in distribution among the lake sites examined, comprising mostly of various heterotrophic populations, with the exception of the Lake Erie-Sandusky Bay site with more than 50% domination by autotrophic Cyanobacteria. This indicates that combinations of factors including water chemistry and various anthropogenic disturbances as well as the lake morphometric characteristics are probably influencing the community structure and diversity of the bacterial assemblages within the systems.