COMPARATIVE AMINO-ACID-SEQUENCE ANALYSIS OF THE MAJOR OUTER CAPSID PROTEIN (VP7) OF PORCINE ROTAVIRUSES WITH G3 AND G5 SEROTYPE SPECIFICITIES ISOLATED IN VENEZUELA AND ARGENTINA

Seven porcine group A rotavirus strains isolated in Venezuela were sho wn to be antigenically related to serotype G3 (five strains) or to ser otype G5 (two strains), whereas two strains isolated in Argentina were classified as serotype G5. The serological classification of eight of these strains was confirmed by sequence analysis of the gene encoding the VP7 glycoprotein. A high degree of homology was observed among st rains belonging to the same G serotype, although some variations in th e serotype-specific regions were detected among different strains. Com parison with the published VP7 amino acid sequences of serotype G3 ind icated that most porcine rotavirus strains are more closely related to each other and to human rotavirus strains than to rotavirus strains i solated from other species. Amino acid sequence comparison among serot ype G5 porcine strains revealed that Venezuelan porcine isolates were more closely related to the American strain OSU, while the Argentinian strains had a higher similarity to the Australian strain TRF-41. This report confirms the worldwide distribution of these G serotypes among the porcine population.