Bicaudaviridae
From MicrobeWiki, the student-edited microbiology resource
A Viral Biorealm page on the family Bicaudaviridae
Contents |
Baltimore Classification
Higher order taxa
Viruses; dsDNA viruses, no RNA stage; Bicaudaviridae
Genera
Description and Significance
Bicaudaviridae is a proposed family of recently discovered crenarchaeal viruses. There is only one isolate in the Bicaudaviridae family. (source: Ortmann et al.)
Genome Structure
The Bicaudiviridae have double-stranded DNA. (source: Ortmann et al.)
Virion Structure of a Bicaudaviridae
Bicaudiviridae virions are spindle-shaped, a morphology unique to the archaeal viral domain. One member of the Bicaudiviridae family, Acidianus two-tailed virus (ATV) is remarkable for the fact that the virus particles develop long tails at each end, a structural transition that happens independent of the host cell. These tails only develop at high temperatures (75-90°C); at lower temperatures, the virus particles retain their tailless spindle shape. (source: Ortmann et al.)
Reproductive Cycle of a Bicaudaviridae in a Host Cell
The basic replication cycle of crenarchaeal viruses, including the Bicaudaviridae, have yet to be determined. The mechanisms for uptake are not known for any of the crenarchaeal viruses. Acidianus two-tailed virus seems to integrate its genome into the host genome. This induction results in a lytic cycle that culminates in lysis of the host. This differs from most other crenarchaeal viruses, which set up chronic infections that do not lyse the host cell. The virions are released when the cell lyses. (source: Ortmann et al.)
Viral Ecology & Pathology
The Bicaudaviridae infect only Acidianus species. According to Ortmann et al., production of ATV particles was not detected when host cells were grown at the optimum growth temperature for the host (85°C). Virion production was triggered by lowering the temperature of cultures to 75°C.
References
Ortmann et al. "Hot crenarchaeal viruses reveal deep evolutionary connections." Nature Reviews Microbiology 4 (2006): 520-528.
