|
Type Species |
(PV) |
Capsid proteins 1B, 1C and 1D of the human enteroviruses are among the largest in the family (VP1-3 chain lengths, 238-302 aa), and this is reflected in the typically long inter--strand loops, the larger than average thickness of the capsid wall (46 Å), and a surface relief that is strongly pronounced compared to most other picornaviruses. Encircling a raised area at the 5-fold axis is a 25-Å deep groove, or “canyon”, into which the cellular receptor for poliovirus binds. The binding site for the pocket factor lies beneath the floor of this canyon within the 1D -barrel. Virions can be converted by a variety of treatments (gentle heating, binding to receptor, or some neutralizing antibodies) to altered (‘A’) particles of 135S which lack VP4 and possess altered antigenicity.
Physicochemical and Physical Properties
Virions are stable at acid pH. Buoyant density in CsCl is 1.30-1.34 g/cm3. Empty capsids are often observed in virus preparations. Sometimes a small proportion (about 1% of the population) of heavy particles (density: 1.43 g/cm3) is observed.
The genome contains no poly(C) tract, and a type-1 IRES. Sequence identities for different enteroviruses, or between enteroviruses and rhinoviruses are more than 50% over the genome as a whole.
Genome Organization and Replication
Genomes encode a single VPg and no L protein. Proteinase 2Apro, which is related to the family of small bacterial serine proteases, cleaves the polyprotein at its own N-terminus. Certain hydrophobic molecules that bind to the capsid in competition with pocket factor exert a powerful antiviral action by interfering with receptor binding and/or uncoating.
Native virions are antigenically serotype specific (designated “N” or “D” for poliovirus), whereas ‘A’ particles exhibit group specificity (designated “H” or “C” for poliovirus).
Viruses primarily multiply in the gastrointestinal tract, but they can also multiply in other tissues, e.g., nerve, muscle, etc. Infection may frequently be asymptomatic. Clinical manifestations include mild meningitis, encephalitis, myelitis, myocarditis and, conjunctivitis. Cap-dependent translation of host mRNA is inhibited by 2Apro, which cleaves the host eukaryotic initiation factor 4G (eIF-4G). Many different cell surface molecules, many of them unknown, serve as viral receptors.
List of Species Demarcation Criteria in the Genus
Members of an enterovirus species:
|
share greater than 70% amino acid identity in P1, |
|
share greater than 70% amino acid identity in the non-structural proteins 2C + 3CD, |
|
share a limited range of host cell receptors, |
|
share a limited natural host range, |
|
have a genome base composition (G + C) which varies by no more than 1%, |
|
share a significant degree of compatibility in proteolytic processing, replication, encapsidation and genetic recombination. |
Swine vesicular disease virus [D00435] is a porcine variant of Human coxsackievirus B5 (CV-B5) [X67706]. Certain viruses initially reported as novel echoviruses were later shown to have been misidentified. Thus E-8 was E-1, E-10 was Reovirus 1, E-28 was Human rhinovirus 1A, E-22 was Human parechovirus 1, E-23 was Human parechovirus 2. Similarly CV-A23 was Human echovirus 9. Porcine enteroviruses belonging to CPE group I have been moved provisionally to a different taxon that may be proposed as a new picornavirus genus.
Official virus species names are in italics. Tentative virus species names, alternative names ( ), strains or serotypes are not italicized. Virus names, genome sequence accession numbers [ ], and assigned abbreviations ( ) are:
|
Bovine enterovirus (2 serotypes) |
(BEV) | |
|
Bovine enterovirus 1 |
[D00214] |
(BEV-1) |
|
Bovine enterovirus 2 |
[X79369] |
(BEV-2) |
|
Human enterovirus A (10 serotypes) |
(HEV-A) | |
|
Human coxsackievirus A2 |
[L28146, X87585] |
(CV-A2)* |
|
Human coxsackievirus A3 |
[X87586] |
(CV-A3) |
|
Human coxsackievirus A5 |
[X87588] |
(CV-A5) |
|
Human coxsackievirus A7 |
[X87589] |
(CV-A7) |
|
Human coxsackievirus A8 |
[X87590] |
(CV-A8) |
|
Human coxsackievirus A10 |
[X87591] |
(CV-A10) |
|
Human coxsackievirus A12 |
[X87593] |
(CV-A12) |
|
Human coxsackievirus A14 |
[X87595] |
(CV-A14) |
|
Human coxsackievirus A16 |
[U05876] |
(CV-A16) |
|
Human enterovirus 71 |
[U22521] |
(EV-71) |
|
Human enterovirus B (36 serotypes) |
(HEV-B) | |
|
Human coxsackievirus B1 |
[M16560] |
(CV-B1) |
|
Human coxsackievirus B2 |
[AF081485] |
(CV-B2) |
|
Human coxsackievirus B3 |
[M88483] |
(CV-B3) |
|
Human coxsackievirus B4 |
[X05690] |
(CV-B4) |
|
Human coxsackievirus B5 |
||
|
(including Swine vesicular disease virus) |
[X67706, D00435] |
(CV-B5) |
|
Human coxsackievirus B6 |
[AF039205] |
(CV-B6) |
|
Human coxsackievirus A9 |
[D00627] |
(CV-A9) |
|
Human echovirus 1 |
[X89531] |
(E-1) |
|
Human echovirus 2 |
[X89532] |
(E-2) |
|
Human echovirus 3 |
[X89533] |
(E-3) |
|
Human echovirus 4 |
[X89534] |
(E-4) |
|
Human echovirus 5 |
[X89535] |
(E-5) |
|
Human echovirus 6 |
[U16283] |
(E-6) |
|
Human echovirus 7 |
[X89538] |
(E-7) |
|
Human echovirus 9 |
[X84981, X92886] |
(E-9) |
|
Human echovirus 11 |
[X80059] |
(E-11) |
|
Human echovirus 12 |
[X79047] |
(E-12) |
|
Human echovirus 13 |
[X89542] |
(E-13) |
|
Human echovirus 14 |
[X89543] |
(E-14) |
|
Human echovirus 15 |
[X89544] |
(E-15) |
|
Human echovirus 16 |
[X89545] |
(E-16) |
|
Human echovirus 17 |
[X89546] |
(E-17) |
|
Human echovirus 18 |
[X89547] |
(E-18) |
|
Human echovirus 19 |
[X89548] |
(E-19) |
|
Human echovirus 20 |
[X89549] |
(E-20) |
|
Human echovirus 21 |
[X89550] |
(E-21) |
|
Human echovirus 24 |
[X89551] |
(E-24) |
|
Human echovirus 25 |
[X90722, X89552] |
(E-25) |
|
Human echovirus 26 |
[X89553] |
(E-26) |
|
Human echovirus 27 |
[X89554] |
(E-27) |
|
Human echovirus 29 |
[X89555] |
(E-29) |
|
Human echovirus 30 |
[X89556] |
(E-30) |
|
Human echovirus 31 |
[X89557] |
(E-31) |
|
Human echovirus 32 |
[X89558] |
(E-32) |
|
Human echovirus 33 |
[X89559] |
(E-33) |
|
Human enterovirus 69 |
[X87605] |
(EV-69) |
|
Human enterovirus C (11 serotypes) |
(HEV-C) | |
|
Human coxsackievirus A1 |
[X87584] |
(CV-A1) |
|
Human coxsackievirus A11 |
[X87592] |
(CV-A11) |
|
Human coxsackievirus A13 |
[X87594] |
(CV-A13) |
|
Human coxsackievirus A15 |
[X87596] |
(CV-A15) |
|
Human coxsackievirus A17 |
[X87597] |
(CV-A17) |
|
Human coxsackievirus A18 |
[X87598] |
(CV-A18) |
|
Human coxsackievirus A19 |
[X87599] |
(CV-A19) |
|
Human coxsackievirus A20 |
[X87600] |
(CV-A20) |
|
Human coxsackievirus A21 |
[D00538] |
(CV-A21) |
|
Human coxsackievirus A22 |
[X87603] |
(CV-A22) |
|
Human coxsackievirus A24 |
[D90457] |
(CV-A24) |
|
Human enterovirus D (2 serotypes) |
(HEV-D) | |
|
Human enterovirus 68 |
[X87604] |
(EV-68) |
|
Human enterovirus 70 |
[D00820] |
(EV-70) |
|
Poliovirus (3 serotypes) |
(PV) | |
|
Human poliovirus 1 |
[J02281] |
(PV-1) |
|
Human poliovirus 2 |
[M12197] |
(PV-2) |
|
Human poliovirus 3 |
[K01392] |
(PV-3) |
|
Porcine enterovirus A (1 serotype) |
(PEV-A) | |
|
Porcine enterovirus 8 |
[AJ001391] |
(PEV-8) |
|
Porcine enterovirus B (2 serotypes) |
(PEV-B) | |
|
Porcine enterovirus 9 |
[Y14459] |
(PEV-9) |
|
Porcine enterovirus 10 |
(PEV-10) |
* Note: The alternative abbreviations, CAV-2, etc., are widely used.
Tentative Species in the Genus
|
Serotypes not yet assigned to a species (22 serotypes) |
|
|
Human coxsackievirus A4 |
(CV-A4) |
|
Human coxsackievirus A6 |
(CV-A6) |
|
Simian enterovirus 1 to 18 |
(SEV-1 to 18) |
|
Simian enterovirus N125 |
(SEV-N125) |
|
Simian enterovirus N203 |
(SEV-N203) |
|
|  |
