Notes on Genus: Salivirus

icosahedra

Type member: Salivirus A

Contents

Members of this Genus
General Description
Morphology
Electron Micrograph
Genome
Genus Genomic Organization
Genome Map
Type Member Genomic Organization
Curated Sequences

General Description

The genus Salivirus (Stool Aichi-like virus) is one of the genera in the family Picornaviridae. Genome organisation is fairly conserved within the family but members of this genus have a leader protease and a distinctive 2A protein which is a putative trypsin-like protease.

Morphology

Virions isometric (icosahedral), not enveloped 30 nm in diameter, made of 60 units (protomers) each consisting of one molecule of each of three surface coat proteins and with a fourth internal capsid protein.

Genome

Monopartite positive sense single-stranded RNA about 8 kb in length. There is a genome-linked protein (VPg) at the 5'-terminus and a 3'-polyA tail.

Genus Genomic Organization

The RNA encodes a single polyprotein that is subsequently processed into the functional products. The major structural proteins are encoded at the N-terminus.

Type Member Genomic Organization

The genome of about 8,000 nucleotides is translated into a single polyprotein, which is subsequently processed into twelve products:
L   12.8 kDa Leader protease
1A+1B   37.6 kDa Coat protein VP4+VP2 precursor
1C 24.4 kDa Coat protein VP3 (surface capsid protein)
1D 29.6 kDa Coat protein VP1 (surface capsid protein)
2A 12.6 kDa non-structural protein (protease)
2B 15.7 kDa non-structural protein
2C 37.8 kDa non-structural protein
3A 8.2 kDa non-structural protein
3B 3.2 kDa Genome-linked protein (VPg)
3C 20.9 kDa protease
3D 52.9 kDa polymerase