Microbiota changes in diseased Hydra magnipapillata

The bacterial community associated with apparently healthy and diseased Hydra magnipapillata was investigated by pyrosequencing analysis of bacterial 16S rRNA. Proteobacteria and Bacteroidetes were the main phyla associated with the apparently healthy specimens. In diseased Hydra, Chlorobi, Cyanobacteria, Planctomycetes and Actinobacteria were also present in addition to Proteobacteria and Bacteroidetes. The diseased specimens were associated with greater abundance of Proteobacteria, Betaproteobacteria, Burkholderiales and Comamonadaceae. The major taxa contained potentially pathogenic bacteria that may influence health of H. magnipapillata. Species diversity and community composition significantly differed between healthy and diseased H. magnipapillata.