Defensive hypervariable regions confer superinfection exclusion in microviruses.

ABSTRACT: Single-stranded DNA phages of the family Microviridae have fundamentally different evolutionary origins and dynamics than the more frequently studied double-stranded DNA phages. Despite their small size (around 5 kb), which imposes extreme constraints on genomic innovation, they have adapted to become prominent members of viromes in numerous ecosystems and hold a dominant position among viruses in the human gut. We show that multiple, divergent lineages in the family Microviridae have independently become capable of lysogenizing hosts and have convergently developed hypervariable regions in their DNA pilot protein, which is responsible for injecting the phage genome into the host. By creating microviruses with combinations of genomic segments from different phages and infecti

SUBMITTER: Kirchberger PC 

PROVIDER: S-EPMC8285946 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature