Family: Inoviridae

Genus: Infulavirus

Distinguishing features

Virions are 900 × 6 nm. The genome of Escherichia phage If1, a member of the species Escherichia virus If1 is 8,454 nt, 47.3% G+C and encodes 10 proteins. Members of the genus Infulavirus are related to members of the genera Inovirus and Lineavirus in terms of the amino-acid sequence of their core genes, but not in their DNA sequences, indicating evolutionary divergence. In addition, members of the genus Inovirus attach to F pili, while infulaviruses attach to the I pilus; there is also a difference in their infectivity mechanisms (Lorenz et al., 2011). The host for infulaviruses is Escherichia coli; a prophage form has not been confirmed although its genome encodes a putative transposase. Infulaviurses form turbid plaques and reduce the size of host colonies, producing substantial cell lysis and cell death. 

Virion

See discussion under family description. 

Genome organisation and replication

See discussion under family description. 

Biology

Members of the genus infect Escherichia coli. 

Species demarcation criteria

There is only one species in the genus. Members of additional species will be >5% different in the DNA sequence of their genomes as assessed using the BLASTn algorithm.