Identification of a G2-like porcine rotavirus bearing a novel VP4 type, P32.

摘要

A porcine group A rotavirus (GARV) strain, 61/07/Ire, was isolated from a 4-5 week asymptomatic piglet, during an epidemiological survey of porcine herds in Southern Ireland, in 2007. The nucleotide (nt) and amino acid (aa) sequence of the full-length VP4 protein of the PoRV strain 61/07/Ire was determined. Based on the entire VP4 open reading frame (nt), strain 61/07/Ire displayed <=76.5 identity to representatives of the established 31 P-types, a value far lower than the percentage identity cutoff value (80) established by the Rotavirus Classification Working Group (RCWG) to define a novel P genotype. Strain 61/07/Ire revealed low aa identity, ranging from 57.1 to 83.6, to the cognate sequences of representatives of the various P genotypes. The aa identity was lower in the VP8* trypsin-cleavage fragment of the VP4, which encompasses the VP4 hypervariable region, ranging from 36.9 to 75.3. Sequence analyses of the VP7, VP6, and NSP4 genes revealed that the GARV strain 61/07/Ire possessed a G2-like VP7, an E9 NSP4 genotype and an I5 VP6 genotype. Altogether, these results indicate that the GARV strain 61/07/Ire should be considered as a prototype of a new VP4 genotype, P32, and provide further evidence for the vast heterogeneity of group A rotaviruses.Digital Object Identifier http://dx.doi.org/10.1051/vetres/2010045