Phylogenetic diversity of cyanophage psbA gene in the different plateau lakes in Yunnan Province

Abstract:

[Objective] Cyanophages are ubiquitous in natural water ecosystems and have an important ecological status and function. They play a role in controlling cyanobacterial populations and community structure by infecting cyanobacteria, which indicates the great application potential of cyanophages in controlling cyanobacterial blooms. This study aims to explore the diversity and phylogenetic status of cyanophage psbA gene in the plateau lakes in Yunnan Province, so as to lay a theoretical foundation for further understanding the ecological role of cyanophages in plateau lakes and exploiting cyanophage resources. [Methods] The psbA gene was used as a molecular target to study the genetic diversity of cyanophages in Dianchi Lake, Fuxian Lake, and Xingyun Lake in Yunnan Province. [Results] A total of 100 psbA sequences of cyanophages were obtained from different lakes. The phylogenetic analysis showed that the psbA gene from the lakes had close genetic distance to those in the East Lake in China, the paddy water in northeast China, and the Japanese paddy floodwater, but were more distantly related to those in the marine waters. The diversity of cyanophage psbA gene in Fuxian Lake was higher than that in Dianchi Lake, Xingyun Lake, and Yilong Lake. The novel psbA assemblies of cyanophage existed in the plateau lakes in Yunnan Province. The genetic diversity of psbA gene showed no significant difference between autumn and winter. [Conclusion] The psbA gene of cyanophages in the main plateau lakes in Yunnan Province has high genetic diversity and is closely related to the psbA gene of cyanophage in freshwater environment. Moreover, there are novel psbA assemblies of cyanophages in the plateau lakes.