Notes on Genus: Inovirus

flexuous filaments
flexuous filaments

Type member: Enterobacteria phage M13


General Description

This is one of the genera in the family Inoviridae. Members are distinguished by having flexuous filamentous particles and because they infect enterobacteria.


Virions are filamentous and slightly flexuous, 7 nm in diameter and 700-2000 nm in length depending on the species. One end is more or less blunt but the other, which has the adsorption proteins for attachment to the bacterial host, may appear pointed in electron micographs.


Monopartite, circular, positive sense, ssDNA, 5-9 kb in length.

Genus Genomic Organization

About 10 ORFs are translated from closely spaced or overlapping genes.

Type Member Genomic Organization

There are 10 closely spaced or overlapping ORFs:
V9.7Heix destabilisation
VII3.6Minor capsid protein: phage assembly
IX3.6Minor capsid protein
VIII7.6Major capsid protein
III44.6Adsorption protein
VI12.3Small hydrophobic
I39.5Phage assembly
IV45.8Phage assembly