Virus found in a boreal lake links ssDNA and dsDNA viruses
Laanto E., Mäntynen S., De Colibus L., Marjakangas J., Gillum A., Stuart DI., Ravantti JJ., Huiskonen JT., Sundberg L-R.
Significance We describe the phage FLiP, an ssDNA virus with an icosahedral capsid and an internal lipid membrane. The FLiP genome shows limited similarity to known sequences, although an ssDNA replication mechanism was implied by genome analysis. However, because the capsid protein fold indicates relatedness with the dsDNA viruses of the PRD1–adenovirus lineage, FLiP exhibits a unique combination of structural and replication modules. It is suggested that the capsid protein structure could be used to complement the sequence data when classifying viruses and in detecting their deep evolutionary relationships, especially in the absence of sequence similarities. Furthermore, these findings demonstrate the value of characterizing unknown viruses from diverse environmental sources to understand the diversity of the microbial world.