Tectivirus

The virus family Tectiviridae (Latin tectus: covered ) comprises only one genus Tectivirus of bacteriophages with linear, double-stranded DNA genome and a 66 nm icosahedral capsid large diameter of 240 capsomeres; the capsomeres composed of trimers of the capsid protein P3. The non-enveloped capsid has at the corners of icosahedral symmetry each a fiber -like projection ( spike ) of about 20 nm in length, which is composed of two proteins (P2 and P5 ), and anchored to the base at a penton protein.

Within (!) Of the capsid is a lipid membrane vesicles, consisting of viral proteins and the lipid membrane of the host bacterium. To discharge of the DNA genome, a tail -like tube of approximately 60x10 nm by the capsid from the inner membrane vesicles everted (hence the naming Tecti - for the property this " hidden " injection apparatus ). This unusual structure of a membrane vesicle within an icosahedral capsid share the Tevtiviridae with the family Corticoviridae. The genome is packaged in a twisted ( coiled ) form within the membrane vesicle. The double-stranded DNA of about 15 kbp in size is Tectiviridae and linked at their 5 ' ends covalently linked to proteins; the prototype of the family, the phage PRD1 coding for 25 viral proteins.

System

  • Genus Tectivirus Species Enterobacteria phage PRD1 (6 subtypes: PRD1, PR3, PR4, PR5, PR722, L17 )
  • Species Bacillus phage AP50
  • Species Bacillus phage Bam35
  • Species Thermus phage P37 -14

Non- classified within the family:

  • Species Bacillus phage ΦNS11 ( = Bacillus thuringiensis phage GIL16c )

Special

  • The hosts of the Tectiviridae are mesophilic bacteria. Only the species Thermus phage p37 -14 infects thermophilic bacteria and is found in volcanic hot springs and geysers.
  • Particularly the phage PRD1 shows very many similarities to members of the Adenoviridae respect to the capsid structure ( hexagonal trimeric capsomers, pentons, fibers ), and the genomic organization (linear dsDNA, so-called inverted terminal repeats, terminal protein, DNA polymerase, type B).
Virus classification National Center for Biotechnology Information Corticovirus Mesophile
763814
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