Distribution of Bacteria and Archaea in meromictic tropical Lake Kivu (Africa)

Aquatic Microbial Ecology

Tamara García-Armisen¹  Jean-Pierre Descy¹  Marc Llirós¹  François Darchambeau¹  Özgül İnceoğlu¹  Sean A. Crowe¹  Celine Michiels¹  Pierre Servais¹ 

关键词: Microbial community;    Stratified lake;    Diversity;    Network;    Pyrosequencing;    qPCR;   

DOI  :  10.3354/ame01737

学科分类：生物科学（综合）

来源: Inter-Research

【 摘 要 】

ABSTRACT: Lake Kivu is a meromictic lake in East Africa with enormous amounts of dissolved methane (CH₄) and carbon dioxide (CO₂) in its deep waters and surprisingly low CH₄ in the surface waters. We applied 454 pyrosequencing of 16S rRNA gene fragments to study the bacterial and archaeal community compositions (BCC and ACC, respectively) to provide insight into the ecology of the microbes in Lake Kivu. The vertical distribution of electron donors and acceptors in the chemically stratified water column may be responsible for the stratified distribution of microbial populations, suggesting well-defined functional specialization. The highest microbial richness was detected in the anoxic zone, which hosted high percentages of bacterial sequences related to uncultured and poorly described phyla. This suggests an under-representation of anoxic environments in current databases and the presence of previously undescribed taxa. Microbial diversity is made up of 2 fractions: abundant species (e.g. Galand et al. 2009) and rare species. Abundant species were more stable than rare species over time. The detection of rare candidate divisions (e.g. OP3, WS3, GN02) co-occurring with sulphur-oxidising Epsilonproteobacteria, sulphate-reducing Deltaproteobacteria, hydrogen-oxidising Dehalococcoidetes and methanogens might indicate interactions in the carbon and sulphur cycles in the anoxic waters.

【 授权许可】

Unknown