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Outbreaks of porcine epidemic diarrhea (PED) in suckling piglets emerged in Jiangxi, China.In order to investigate the epidemiology and genetic characterization of porcine epidemic diarrhea viruses (PEDV), causative agents of the outbreaks, a pair of primers was designed to amplify both E and M gene of the PEDVs.In this study, E gene and M gene of eight strains of PEDV isolated in Jiangxi in 2013 were sequenced.Sequence analyses revealed that the identities of the nucleotide (nt) and deduced amino acid (aa) sequences of the E gene of these isolates ranged from 96.1-100% and 97.4-100%, respectively, when compared to each other, and had a 95.2%-100% nt and 94.2% deduced aa sequence identities with selected reference strains.When compared to CV777, a vaccine strain, one aa mutation at the position of 42 (H42R) in the E gene of strain JXYCI301 and two aa mutations at the position of 42 (Q42R) and 66 (I66M) in the E gene of strainJXSR1301 were identified.The sequences of M genes of the eight Jiangxi isolates shared 97.9-100% nucleotide and 98.2-100% amino acid sequence identities with each other, while 97.7-100% and 97.4-100% similarity to selected reference strains, respectively.Phylogenetic trees based on both E and M gene, were constructed.All the sequences of the E gene analyzed in this study were group into two genotypes.Except for the isolate JXNC/1302, the other seven Jiangxi isolates belonged to group 1 (G1), together with the strains isolated before 2010 from China, Korea and USA.Phylogenetic analysis of the M gene had a similar topology with that of E gene.Both 2013 Jiangxi strains and reference strains fell into two groups.Amino acid mutations were observed between the two genotypes.Those mutations might have altered in terms of immunogenicity of the field PEDV isolates.