Bar-Coded Pyrosequencing Reveals the Bacterial Community during Microcystis water Bloom in Guanting Reservoir, Beijing

An understanding of bacterial community composition is a fundamental goal of identifying ecological efficiency caused by Microcystis bloom in aquatic system. In this study, we employed bar-coded 454 pyrosequencing approach to investigate the bacterial community variation during a Microcystis water bloom in Guanting Reservoir, Beijing. More than 140,000 sequences were generated and assigned to 7133 operational taxonomic units (OTUs) which belong to 18 phyla through Ribosomal Database Pyrosequencing (RDP) database. Microcystis was detected at low abundance in July then broke out and became the exclusive dominant genus in September. Meanwhile, bacteria composition changed dramatically after the Microcystis water bloom reflected by the decrease of bacteria abundance, diversity and evenness indices. The classify results indicated that dominant species in July were Pelagibacter, Haliscomenobacter, Rhodobacter and Fluviicola. In September, Methylotenera, Flavobacterium and Methylophilus were the dominant genera. It is worth noticing that all the dominant genera in July was more or less related to nitrogen and phosphorus cycling while in September, dominant genera Flavobacterium was reported as Microcystis lysing bacterium and may be a symptom of the coming postbloom phase of Microcystis water bloom in Guanting Reservoir.