Stanway G (Chairman), Brown F, Christian P, Hovi T, Hyypiä T, King AMQ, Knowles NJ, Lemon SM, Minor PD,  Pallansch MA, Palmenberg AC, Skern T.

Assign A-2 plaque virus and simian viruses 4 and 28 as members of a new species, Simian enterovirus A, of genus Enterovirus.

1.1   Purpose

The complete genome sequence of A-2 plaque virus has been published (Liu et al., 2000). This reveals that the virus, currently an unassigned enterovirus, is Enterovirus-like in terms of genome organisation and in the coding region is more closely related to members of this genus than to any other picornaviruses.  However, it does not fall into any of the existing Enterovirus species as it shares less than 70% amino acid identity with any other species in both the P1 and 2C+3CD regions (members of an enterovirus species must share at least 70% identity).  Phylogenetic trees of enteroviruses representing each species make clear its distinct nature and the need to create a new species (Fig.1). A-2 plaque virus was first isolated from the icteric-phase sera of a patient with viral hepatitis. However, it is isolated rarely from humans and recent analysis of enteroviruses isolated from simians has revealed viruses closely-related (>95% amino acid identity in VP1) to A-2 plaque virus, notably simian enterovirus 4 (SE4) and SE28 (Oberste et al., 2002).  It is therefore proposed to name the new species Simian enterovirus A (SEV-A). The designation A is employed, as partial sequence analysis of other simian viruses suggests that further Simian enterovirus species will need to be created in the future.

1.1   Revised organisation of the taxon

The Enterovirus genus will now consist of 9 species:

Poliovirus (type species)

Human enterovirus A through D

Bovine enterovirus

Porcine enterovirus A,B

Simian enterovirus A

1.3     Derivation of proposed name

The name and abbreviation derives from the presumed host tropism and the current convention.

1.4     References

Accession Nos.

AF201894 [A2 plaque virus]
AF326757 [SV28]
AF326759 [SV4]

Liu Z, Donahue RE, Young NS, Brown KE (2000) Sequencing and characterization of A-2 plaque virus: A new member of the picornaviridae family. Virology 272:168-176.

Oberste MS, Maher K, Pallansch MA (2002) Molecular phylogeny and proposed classification of the simian picornaviruses.  Journal of Virology 76:1244-1251.

Define species criteria for the genus Kobuvirus and assign U-1 virus as a member of a new species, Bovine kobuvirus (BKV), of this genus. 

2.1          Purpose

The sequence of a virus (strain U-1) related to Aichi virus, a member of the Kobuvirus genus has been recently published (accession AB084788). It has typical Kobuvirus-like molecular features, but is divergent from Aichi virus in amino acid sequence terms by an extent similar to that seen between species in other Picornaviridae genera. It is proposed to define species criteria for the kobuvirus genus and assign U-1 as a member of a new species within the genus. In view of the limited number of kobuvirus sequences available, the species criteria proposed are based on those used for several Picornaviridae genera. The definition proposed is

“Members of a Kobuvirus species:

Share greater than 70% amino acid identity in the P1

Share greater than 70% amino acid identity in the 2C+3CD

Have a common genome layout”

By these criteria U-1 does not belong to the single existing Kobuvirus species, Aichi virus and it is proposed to create a new species. As the new virus appears to be associated with cattle, the proposed species name is Bovine kobuvirus (BKV). The relationship between Picornaviridae species, including BKV, can be seen in Fig. 3 (2C+3CD) and Fig. 4 (P1).

2.2     Revised organisation of the taxon

     As a result of this proposal the Kobuvirus genus will include two species:

     Aichi virus                   (AiV)

     Bovine kobuvirus         (BKV)

2.3          Derivation of proposed name

The proposed species name is based on the association of the virus with cattle.

2.4     References

Yamashita T, Ito M, Kabashima Y, Tsuzuki H, Sakae K  (2002) Isolation and characterization of a new species of kobuvirus associated with bovine (Unpublished)

     Accession No. AB084788