Molecular Diversity of Cyanopodoviruses in Two Coastal Wetlands in Northeast China.

Although bacteriophages are the most abundant biological entities on the planet, their genetic diversity, especially in natural wetlands, is poorly understood. In this study, the genetic diversity of cyanopodoviruses in sediments of two coastal wetlands in Northeast China was investigated by targeting the DNA polymerase (pol) gene. A total of 66 DNA pol clones were obtained. A BLAST search at the amino acid level showed that the obtained sequences had the highest identity ranged from 83 to 99% to the known sequences. A phylogenetic tree showed that the distribution patterns of DNA pol sequence were different between two wetland soils, and 29 clones of this study formed four wetland-specific groups, which suggested that unrevealed novel groups of cyanopodovirus inhabited in wetlands. In addition, nonmetric multidimensional scaling (NMDS) analysis of all DNA pol sequences from various environments showed that cyanopodovirus communities of coastal wetlands are in the intermediate position between marine water environments and terrestrial freshwater environments, which highlights that the coastal wetlands as transitional zones between inland freshwater environments and marine environments.