Analysis of aerobic anoxygenic phototrophic bacterial community structure in the different marine functional zones in the Zhoushan Archipelago Sea Area in summer

Aerobic anoxygenic phototrophic bacteria (AAPB) containing bacteriochlorophyll a (BChl a) are photoheterotrophic prokaryotes that are a widely distributed functional bacterial group due to their obligately aerobic and facultative photoheterotrophic abilities. Here, we made a comparison of AAPB community structures in different marine functional zones in the surface water of the Zhoushan Archipelago Sea Area using high-throughput sequencing based on the pufM gene that encodes the M subunit of the light reaction centre complex. A total of 268,214 clean reads were obtained from the sampling stations. The sequences were divided into 5876 OTUs (97% cut-off value). Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria phyla were noted in this study. Proteobacteria phylum accounted for the major proportion and existed at all sites. Roseobacter-like AAPB was the most abundant genus, in Dongji Island (DJ) and Gouqi Island (GQ). Our results demonstrated that the structure of the AAPB community had different distribution patterns within the Zhoushan Archipelago Sea Area. Furthermore, we found that the diversity of AAPB was controlled by complex environmental factors, which might explain the difficulties encountered when predicting the distribution of total AAPB in aquatic ecosystems.