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Objective@#By investigating the genotype and evolutionary variation of hantavirus (HV) in Tiantai county, a national surveillance site for hemorrhagic fever with renal syndrome (HFRS) was set in Zhejiang province, from 2011 to 2018, to reveal the molecular epidemiological characteristics of hantavirus (HV) in Tiantai.@*Methods@#Total RNA was extracted from ultrasound treated HV antigen- positive rat lung samples in Tiantai from 2011 to 2018. After cDNA was prepared, nested PCR was used to amplify partial sequence of M fragments by using specific primers of HV. The sequences of HV in Tiantai from 2011 to 2018 were compared with other known HV sequences in order to identify the genotype and analyze the evolution and variation of the virus.@*Results@#In 67 HV antigen-positive lung specimens, 31 were positive in nested PCR amplification with type-specific primers, including 30 Hantaan virus (HTNV) positive samples, 1 Seoul virus (SEOV) positive sample, and all the 31 samples were from Apodemus agrarius. The phylogenetic tree based on partial M segment was divided into monophyletic group, 30 strains were distributed in HTNV group and 1 was in SEOV group. The HTNV strain Tiantai T2018-130 was independently in one branch, sharing 84.8%-87.9% homology with other strains both at home and abroad, including 29 strains in HTNV group in Tiantai. The other 29 HTNV strains in Tiantai showed closer relationship. The SEOV strain T2016-31 from Apodemus agrarius showed closer relationship with previous strains of SEOV, Tiantai ZT71, ZT10 and Z37 strains of Wenzhou, Zhejiang province.@*Conclusions@#HTNV, the main genotype of HV in Tiantai of Zhejiang province, showed obvious geographic clustering, but the strain T2018-130 was distinct from the others in Tiantai. Meanwhile, by sequence analysis, we confirmed that The SEOV strain T2016-31 existed in in Apodemus agrarius, indicating there was a phenomenon of "spillover" between virus and host in SEOV evolution.
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Objective@# To learn the population,virus status and viral types of hantavirus（HV）hosts in Tiantai County of Zhejiang Province from 2011 to 2018,and to provide evidence for hemorrhagic fever with renal syndrome（HFRS）control. @*Methods@# Rodents in Tiantai County were captured by night trapping method. After the species and age of rodents were identified,the composition of rodent species,dominant species and density of rodents were analyzed. The lungs and blood of rodents were sampled to detect the antigen and antibody of HV by immunofluorescence method. The HV antigen-positive lung samples were detected by RT-PCR with specific primers of HV S fragment,then HV was isolated and identified by inoculating Vero-E6 cells.@*Results@# The average rodent density in Tiantai County from 2011 to 2018 was 4.44%. The rodent density in the field and residential areas were 4.94% and 2.23%,respectively. Ten species of rodents were identified,with Apodemus agrarius dominant in the field and Rattus norvegicus in the residential areas. Sixty-seven lung samples were HV antigen positive（4.13%）,one from Rattus norvegicus and the other sixty-six from Apodemus agrarius. Seventy-nine blood samples were HV antibody positive（4.86%）,all from Apodemus agrarius. Thirty-four HV antigen-positive lung samples were positive（50.75%）after RT-PCR amplification. Twenty-two strains of virus were isolated and all of them were from Apodemus agrarius,including twenty-one strains of Hantaan type（HTN）and one strain of Seoul type（SEO）.@*Conclusion @#In Tiantai County,Apodemus agrarius is the main source of HFRS infection;the main epidemic type of HV is HTN and SEO is first found in Apodemus agrarius.
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Objective S gene of hantavirus(HV) was expressed in insect cells by genetic engineering technology.The expression product of S gene was used as antigen to detect anti-HV specific antibody IgG in serum.Methods Gene encoding NP of the strain HV-Z10 was amplified by PCR and then its eukaryotic expression system rBAC-Z 10S-TN was constructed by using the routine genetic engineering method.SDS-PAGE was applied to measure the expression of rNP.Ion-exchange plus Ni-NTA-affinity chromatography was performed to purify the recombinant product.Indirect immuno-fluorescence assay (IFA) was used to determine the specific immune-reactivity of rNP.WB assay was established to detect the serum samples from 95 confirmed HFRS patients.Parameters related to the outcomes of detection were compared with the routine HV-IgG IFA method.Results rBAC-Z10S-TN was able to express rNP with high efficiency.The purified rNP only showed a single protein fragment in the gel after SDS-PAGE.HV IgG could efficiently recognize rNP and hybridize with the recombinant protein.97.67％ of the serum samples from the HFRS patients were positive confirmed by WB.Conclusions We successfully constructed a high efficient prokaryotic expression system of NP encoding gene from hantavirus strain HV-Z10.WB assay which was established in this study could be used as a new serological test for HFRS diagnosis,thanks to the simplicity,safety,sensitivity and specificity of this method.
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Objective S gene of hantavirus(HV) was expressed in insect cells by genetic engineering technology.The expression product of S gene was used as antigen to detect anti-HV specific antibody IgG in serum.Methods Gene encoding NP of the strain HV-Z10 was amplified by PCR and then its eukaryotic expression system rBAC-Z 10S-TN was constructed by using the routine genetic engineering method.SDS-PAGE was applied to measure the expression of rNP.Ion-exchange plus Ni-NTA-affinity chromatography was performed to purify the recombinant product.Indirect immuno-fluorescence assay (IFA) was used to determine the specific immune-reactivity of rNP.WB assay was established to detect the serum samples from 95 confirmed HFRS patients.Parameters related to the outcomes of detection were compared with the routine HV-IgG IFA method.Results rBAC-Z10S-TN was able to express rNP with high efficiency.The purified rNP only showed a single protein fragment in the gel after SDS-PAGE.HV IgG could efficiently recognize rNP and hybridize with the recombinant protein.97.67％ of the serum samples from the HFRS patients were positive confirmed by WB.Conclusions We successfully constructed a high efficient prokaryotic expression system of NP encoding gene from hantavirus strain HV-Z10.WB assay which was established in this study could be used as a new serological test for HFRS diagnosis,thanks to the simplicity,safety,sensitivity and specificity of this method.
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To explore the molecular characteristics of Streptococcus suis serotype 2(ss2) isolated in Zhejiang province by deciding the variation loci and its variation frequency of Cps2J gene.The total DNA of 9 strains of ss2 isolated in Zhejiang province were extracted and amplifed by PCR. Then,the Cps2J fragments were cloned into plasmid carrier and completely sequenced after purification.Finally,the sequence results of all 9 ss2 isolates were compared with those obtained by other studies around the world.It was found that the open reading fragments of Cps2J in 9 SS2 isolates encoding 333 amino acids were 999 bp in length.Comparisons of this region among ss2 isolates revealed a similarity of between 98.8% and 99.9%, while the homology to ss1 strains varied between 56.8% and 57.0%.Our study shows the sequences of complete Cps2J segment are fairly stable and all these 9 ss2 strains of different sources possibly have the same evolutionary origin.
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The M and S segment cDNAs of hantavirus Z5 strain was amplified by RT-PCR,and the purified PCR products were cloned into vector pGEM-T and then sequenced.It was demonstrated that the M genome segment of Z5 was found to be 3 616 nucleotides in length with a single open reading frame encoding 1 135 amino acids.And the S genome segment was 1700 nucleotides in length with a single open reading frame encoding 429 amino acids.As demonstrated by the homologous analysis of nucleotides and amino acids,it was showed that the Z5 strain belonged to hantaan viruses HTN type and was the same subtype of the Z10 strain.It is conclouded that difference in nucleotide sequence exists between Z5 strain with other Hantavirus strains but high level of homology in amino acid sequences is still present.
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One strain of Hantavirus(HV) was isolated from patients with hemorrhagic fever with renal syndrome (HFRS) in Zhejiang province and its S-segment was cloned and submitted to nucleotide sequence analysis in order to determine the type of strain and extent of genetic variation for further study on its evolution and mutation .The HV antigen was detected from mouse lungs in endemic area by direct immunofluorescene test and the HV-positive sample of mouse lung was inoculated to Vero-E6 cells to isolate virus. The total cellular RNA was extracted from infected cell culture and the S segment gene was amplicated by RT-PCR. Then, the purified PCR product was cloned into T vector for sequencing. The result showed that the full-length sequence of the S segment was 1 700 bp with one open reading frame (ORF) encoding 429 amino acids. Comparison with Hantavirus HTN type showed 85.7%-91.9% homology at the nucleotide level. In comparison with the SEO type of viruses, the homology at nucleotide level was shown to be 71.2%-75%. This new HV strain may be typed as to HTN virus and may be a new subtype of this virus.
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Objective To study the complete genome sequence of Hantavirus ZT71 strain gene isolated in Zhejiang province and explore its evolution. nethods The total RNA was prepared from ZT71 virus infected cells and the RT-PCR products were cloned into T vector, sequenced and analyzed. Results The L, M and S segments of the strain ZT71 genome were 6530,3651 and 1753 nucleotides in length with a single open reading frame individually encoding 2151,1133 and 429 amino acids. The sequence analysis of nucleotides showed that the homology of L, M and S segments of strain ZT71 between those of other strains of Seoul virus could reach 95.5%-99.7%, 84.1%-99.6% and 88.7%-99.5%, respectively. The analysis of the deduced amino acids showed the similar result. The source of strain ZT71 could be traced from the analysis of the phylogentic trees of nucleotides and amino acids, and it should belong to Seoul type of Hantavirus which was also verified serologically. Conclusion The nucleotide sequences and deduced amino acid sequences of L, M and S segments of strain ZT71 are similar to that of those of Seoul type of Hantavirus. And Hantaan type virus used to be prevalent primarily in Zhejiang province,and it would be an endemic area of mixed type of Hantavirus since the discoveries of the viruses of Soeul type in recent years.
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Objective To compare the molecular characteristics of hantanvirus strains isolated from 1980 to 2002 in Zhejiang Province by PCR and nucleotide sequencing.Methods Total RNA was extracted from hantanvirus infected Vero-E6 cells. The M segment cDNA of hantaan ZJ4 and ZJ7 strains were obtained by reverse transcription and polymerase chain reaction, subsequently cloned into pUCm-T vector and sequencing.Results Two strains ZJ4 and ZJ7 of hantanvirus isolated from Rottus in Zhejiang province were HTN viruses. HTN virus strain Z10 was isolated in 1980. Comparison ZJ4 and ZJ7 with Z10 strains indicated that there were 88.3% and 92.3% homology at the nucleotide level.Conclusion The HTN virus were very conserved. The homology of HTN virus isolated from Zhejiang Province was high nucleotide level, though they were isolated at more than 20-year intervals.
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<p><b>OBJECTIVE</b>To study the severe acute respiratory syndrome (SARS)-associated coronavirus genotype and its characteristics.</p><p><b>METHODS</b>A SARS-associated coronavirus isolate named ZJ01 was obtained from throat swab samples taken from a patient in Hangzhou, Zhejing province. The complete genome sequence of ZJ01 consisted of 29,715 bp (GenBank accession: AY297028, version: gi: 30910859). Seventeen SARS-associated coronavirus genome sequences in GenBank were compared to analyze the common sequence variations and the probability of co-occurrence of multiple polymorphisms or mutations. Phylogenetic analysis of those sequences was done.</p><p><b>RESULTS</b>By bioinformatics processing and analysis, the 5 loci nucleotides at ZJ01 genome were found being T, T, G, T and T, respectively. Compared with other SARS-associated coronavirus genomes in the GenBank database, an A/G mutation was detected besides the other 4 mutation loci (C:G:C:C/T:T:T:T) involved in this genetic signature. Therefore a new definition was put forward according to the 5 mutation loci. SARS-associated coronavirus strains would be grouped into two genotypes (C:G:A:C:C/T:T:G:T:T), and abbreviated as SARS coronavirus C genotype and T genotype. On the basis of this new definition, the ZJ01 isolate belongs to SARS-associated coronavirus T genotype, first discovered and reported in mainland China. Phylogenetic analysis of the spike protein gene fragments of these SARS-associated coronavirus strains showed that the GZ01 isolate was phylogenetically distinct from other isolates, and compared with groups F1 and F2 of the T genotype, the isolates of BJ01 and CUHK-W1 were more closely related to the GZ01 isolate. It was interesting to find that two (A/G and C/T) of the five mutation loci occurred in the spike protein gene, which caused changes of Asp to Gly and Thr to Ile in the protein, respectively.</p><p><b>CONCLUSION</b>Attention should be paid to whether these genotype and mutation patterns are related to the virus's biological activities,epidemic characteristics and host clinical symptoms.</p>