Group Group I (dsDNA) Order Caudovirales | Rank Subfamily | |
People also search for Podoviridae, Phikmvlikevirus, T7likevirus | ||
Autographivirinae is a subfamily of viruses in the order Caudovirales, in the family Podoviridae. Bacteria serve as natural hosts. There are currently 15 species in this subfamily, divided among 3 genera.
Contents
History
Since the 1990s, the term "T7 supergroup" has been coined for the expanding group of bacteriophages related to coliphage T7, as members of the family Podoviridae. Enterobacteriaceae phages SP6 and K1-5 were the first to be considered as an estranged subgroup of the "T7 supergroup". Pseudomonas phage phiKMV also shared commonalities at the genome organizational level. As such, based on the available morphological and proteomic data, this clade of viruses was established as a subfamily of the Podoviridae family.
Definition
The name of this subfamily, termed Autographivirinae, refers to the “auto-graphein” or “self-transcribing” phages which encode their own (single subunit) RNA polymerase, a common characteristic among its members.
Structure
Viruses in Autographivirinae are non-enveloped, with icosahedral and Head-tail geometries, and T=7 symmetry. The diameter is around 60 nm. Genomes are linear, around 40-42kb in length.
Life Cycle
Viral replication is cytoplasmic. Dna templated transcription is the method of transcription. The virus exits the host cell by lysis, and holin/endolysin/spanin proteins. Bacteria serve as the natural host. Transmission routes are passive diffusion.
Taxonomy
Group: dsDNA
Currently, the Autographivirinae are subdivided in three genera: T7likevirus, Phikmvlikevirus, and Sp6likevirus. Unclassified members include cyanophages P60, syn5 and P-SSP7. Other bacteriophages like Bacteriophage SIO1 and VpV262 are evolutionary related to the Autographivirinae, but do not contain a phage-encoded RNA polymerase and show greater differences at the genome organization level. Another genus may be formed by the phages Cronobacter sakazakii Bacteriophage vB_CsaP_GAP227, Yersinia phages ϕR8-01 and ϕ80-18 and Aeromonas phage phiAS7.
Another group in this family are the cyanopodoviruses.