ABSTRACT
To select the adaptive strain of Dengue-III virus D9964 strain (China strain) in KMB17 cells, elucidate the biological characteristics and proliferation kinetics of adapted strain,and to lay the foundation for the development dengue inactivated vaccine and attenuated live vaccine. Dengue-III virus D9964 strain was firstly identified by amplification of the type-specific gene segment of dengue virus by RT-PCR, and the titer was determined. The virus was then subcultured in KMB17 cells with 4.0 MOI till completely adaptive to multiply in cell S. After subculturing in KMB17 cells for 10 consecutive passages, the adapted strain was screened, and purified through plaque. Virus titer of each passage was measured by microtitrimetry, and the antigenicity was detected by IFA. The purified virus RNA extraction of 3-8 day cultured from KMB17 cells, was performed to detect the proliferation kinetics of adapted strain. The results showed that after continuous subculture, dengue-III virus D9964 (China) strain could stably proliferate in KMB17 cells, a highly puried virus adapted strain was obtained through plaque purification. Purified strain maintained the good antigenicity with a highest replicating activity during the 5th-6th day.
Subject(s)
Humans , Cell Line , Dengue , Virology , Dengue Virus , Chemistry , Genetics , Physiology , Kinetics , Virus Cultivation , Virus ReplicationABSTRACT
To analyze the genomic sequence characteristics of a human Echovirus 9(ECHO-9) strain isolated from a child with Hand-foot-mouth disease (HFMD) in Kunming, Yunnan Province, in 2010. The complete genome sequence of a human echovirus 9 strain, MSH-KM812-2010 was determined. As other human enterovirus, its genome was 7,424 nucleotides (nts) in length and encoded for 2,203 amino acids (aas). In comparison to other human enteroviruses, MSH-KM812-2010 strain had the highest homology with other strains of human echovirus 9 in structural genomic regions and more homologous to other serotypes of B specie than to human echovirus 9 in non-structural genomic regions. Phylogenetic analysis based on complete VP1 gene revealed that the sequences of human echovirus 9 segregated into three distinct clades A, B and C with more than 15. 0% diversity between clades. All Chinese isolates belonged to the same clade. RDP3 and Blast revealed evident recombination in non-structural genomic regions. This report is the first to, describe the complete genome of the human echovirus 9 in China and provide an overview of the diversity of genetic characteristics of a circulating human echovirus 9.
Subject(s)
Female , Humans , Infant , Base Sequence , China , Echovirus 9 , Classification , Genetics , Genome, Viral , Molecular Sequence Data , Phylogeny , Viral Proteins , GeneticsABSTRACT
Objective To describe the genetic characterization of complete genome from a human coxsackievirus A16 (CA16) strain KMM08,isolated in Yunnan,China,in 2008.Methods By using RT-PCR,the seven fragments contained about 1000 nucleotides in the complete genome were sequenced.The sequences were aligned with other enterovirus sequences downloaded from GenBank using Mega 4.1,RDP3 and SimPlot 3.5.1 software.Results As in other human enterovirus,its genome was 7409 nucleotides in length,encoding for 2193 amino acids.KMM08 strain was closely related to other reference strains of B genotype.In the complete genome,the homology of nucleotide and amino acid among the eleven CA16 isolated strains were 79.0％-98.2％ and 94.5％-99.3％,respectively.The rates of homology were 79.1％ and 94.8％ when comparing with that of G10 strains and 78.7％ and 89.0％ comparing with that of BrCr strains,respectively.SZ-HK08-3 strain had high homology when compared to other strains.In different segment of genome,the rates of homology were 97.0％-99.0％ and 98.0％-100.0％ when compared with that of SZ-HK08-3 strains,respectively.The rates of homology were 74.2％-86.9％ and 90.9％-97.0％ when compared with that of G10 strains,respectively and were 65.0％-84.9％ and 71.0％-95.2％ when compared with that of BrCr strains.Data from Phylogenetic analysis showed that KMM08 belong to genotype B.The putative recombinant Tainan-5079-98 was detected positive with RDP3 and SimPlot 3.5.1.Conclusion KMM08 strains isolated in Yunnan in 2008 belonged to B genotype of coxsackivirus A16.The possible occurrence of inter-typic recombination would involve EV71 and CA16.
ABSTRACT
Objective To analyze genetic characterization of the small hydrophobic and hemagglutinin-neuraminidase genes of mumps virus(MuV)isolated in Yunnan province,China from 2007 to 2009.Methods Fourteen MuV strains were isolated in Yunnan,China from 2007 to 2009.Using RT-PCR,the SH gene fragments contained 316 nucleotides in all strains and HN gene of six strains were sequenced.The sequences were aligned with other mumps virus sequences downloaded from GenBank using Mega 4.1 software.Results Fourteen isolated strains were closely related to other reference strains of F genotypes.In SH gene,the homology of nucleotide and amino acid among the fourteen isolated strains were 98.3%-100.0%and 96.5%-100.0%,respectively,and 92.6%%-99.4%and 87.7%-100.0% of homology when compared with that of strains isolated from other provinces in China,respectively.Wsh1 and Wsh2 strains had less homology when compared to other strains of F genotypes.The fourteen strains had homology of 84.5%-85.1%and 77.2%compared to vaccine strains on nucleotide and amino acid,respectively,and had homology of 83.4%-90.9% and 70.1%-86.0% compared to that of other genotypes.In HN gene,the homology of nucleotide and amino acid among the six isolated strains were 99.3%-99.5% and 99.1%-99.7%,respectively,and also 99.8% and 99.8% of homology respectively when compared to the SP strain in China.All the six strains had homology of 92.4%-93.2% and 95.5%-96.4% when compared to the vaecine strains on nucleotide and amino acid,respectively,and had homology of 94.7%-96.8% and 95.5%-99.1%compared to other genotypes.Conclusion Fourteen strains isolated in Yunnan from 2007 to 2009belonged to F genotype of MuV while the HN gene seemed more conservative than SH gene.
ABSTRACT
The proteins encoded by the Herpesviridae β-gene play a critical role in the replication stage of the virus. In this paper, phylogenetic analyses provided evidence that someβ-gene products, such as UL2 and UL23 from HSV1, have their homologous genes in its family, and also exist in prokaryotic organisms, indicating that these viruses appear to have been assembled over evolutionary time by numerous independent events of horizontal gene transfer.