Community Structure of Bacteria Associated with<i>Microcystis</i>Colonies from Cyanobacterial Blooms

Abstract

ABSTRACT Thirty Microcystis colonies, belonging to three species (Microcystis aeruginosa, Microcystis flos-aquae, and Microcystis wesenbergii) were isolated from Lake Taihu and Lake Chaohu in China. Bacterial communities associated with the single Microcystis colonies were investigated using a seminested polymerase chain reaction-amplification along with denaturing gradient gel electrophoresis (DGGE). The bacterial communities of most colonies of the same Microcystis species in each lake tended to be similar. This indicates that species-specific associations may exist between colony-associated bacteria and Microcystis spp. Sequence analysis of dominant DGGE bands revealed that the dominant bacterial groups associated with Microcystis colonies were Alphaproteobacteria, Betaproteobacteria, Garnmaproteobacteria, Bacteroidetes, Firmicutes, Deinococcus-Thermus, and Gemmatimonadetes. Phylotypes related to Pseudomonas sp., Serratia sp., and Flexibacteraceae were dominant in colonies of M. wesenbergii, M flos-aquae, and M aeruginosa, respectively.