Notes on Genus: Enamovirus


Type member: Pea enation mosaic virus-1


General Description

The genus Enamovirus (from the type member pea enation mosaic virus 1) is one of three genera in the family Luteoviridae and currently has only one member. Until recently it was considered as an irreversible mixed infection of two autonomously replicating RNAs, but the current taxonomy retains only the old RNA1 (which has some similarity to members of the genus Polerovirus) as an enamovirus and places the old RNA2 as a different virus (Pea enation mosaic virus-2) in the genus Umbravirus.


Virions isometric (polyhedral), not enveloped, of two sizes, 25 and 28 nm in diameter.


Monopartite, linear, single stranded, positive sense RNA about 5700 nt long. The 3'-terminus has neither a poly(A) tract nor a tRNA-like structure, and the 5'- terminus has a genome-linked protein.

Genus Genomic Organization

The genome (5706 nucleotides) has many similarities to members of the genus Polerovirus but lacks the functions for systemic movement and mechanical transmission, which are supplied by Pea enation mosaic virus-2, in the genus Umbravirus, with which it is invariably associated. .

Type Member Genomic Organization

There are five ORFs:
1.  ORF 0 34 kDaunknown function
2.  ORF 1 84 kDa Replication protein
3.  ORF 2 67 kDaPolymerase
4.  ORF 3 21 kDaCoat protein
5.  ORF 5 54 kDaCoat protein readthrough
These ORFs are numbered to be consistent with other members of the family Luteoviridae.