Marine Science Faculty Publications



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Members of the Microviridae comprise at least two subfamilies (Bullavirinae and Gokushovirinae), with divergent sequences from many uncultured representatives yet to be formally classified. Bullaviruses (canonical species φX174), which infect free-living bacteria, are among the fastest known replicating viruses. Gokushoviruses were originally thought to occupy a unique niche, infecting obligate intracellular bacteria; however, genomic analyses suggest that this group infects free-living hosts as well. Some gokushoviruses, unlike other members of the family, can undergo both lytic and lysogenic replication cycles. Microviridae contain small (4000–6000 bases), circular and single-stranded deoxyribonucleic acid (ssDNA) genomes of positive polarity, which are packaged inside small (∼25 nm diameter) T = 1 icosahedral capsids. The most well-known member of the Microviridae, φX174, has been fundamental in uncovering the mechanisms of DNA replication and capsid assembly and become a model system for experimental evolution. In contrast, little is known about the replication, structure and host range of gokushoviruses despite viromics indicating their ubiquity throughout the biosphere.

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Microviridae, in John Wiley & Sons, Ltd (Ed.), eLS, Wiley