SH protein genetic characterization analysis of wild-type mumps virus isolated in Liaoning province from 2008 to 2011 / 病毒学报

ABSTRACT

A total of 13 mumps virus strains were isolated using Vero/Slam cell line from the patients' throat swabs and urines during mumps outbreaks and sporadics in liaoning Province from 2008 to 2011. Fragments of 316 nucleotides containing SH genes from 13 mumps virus isolates were amplified by RT-PCR, the PCR products were sequenced and analyzed. Based on the 316 nucleotides of SH gene, the phylogenetic trees were constructed with WHO mumps reference strains downloaded from GenBank and 13 mumps virus strains. It showed that the 12 mumps virus strains in 2008-2011 belonged to F genotype, nucleotide acids and amino acids similarities were 94.9%-100.0% and 83.3%-100.0%. Compared to the F reference strains, nucleotide acids and amino acids similarities were 92.4%-97.2% and 96.5% 84.2%, indicating that liaoning mumps strains had large genotype variation. Furthermore, compared to other genotype mumps strains, 6 nucleotides mutations (C(Nt65), C(Nt105), G(Nt137), C(Nt192), C(Nt239), G(NT262)) in SH gene were shared in all of liaoning F genotype mumps viruses. However these mutations were not found in other genotypes of mumps viruses. Conserved amino acids in SH protein of some liaoning mumps strains had changed (S to P at position 2 P to L at position 6 T to N at positon 23 L to P/R at position 48). The genotype specific triplet IML (at position 28-30) was changed to TMP in strain 2008-001-007 2011-015 s, nucleotide acids and amino acids similarities of strain 2008-001-07 were 87.5% and 79.8%, compared to F reference strains respectively, and 96.8% and 97.4% respectively compared to the G reference strains, in dicating strain 2008-001-07 belonged to G genotype,which was first found in mainland China.