目的建立针对食品来源的单核细胞增生李斯特氏菌(Listeria monocytogenes,Lm)分离株的多位点串联重复序列分型(Multiple-Locus Variable number tandem repeat Analysis,MLVA)方法,为暴发确认和溯源检测提供实验室支持。方法对2005—201...目的建立针对食品来源的单核细胞增生李斯特氏菌(Listeria monocytogenes,Lm)分离株的多位点串联重复序列分型(Multiple-Locus Variable number tandem repeat Analysis,MLVA)方法,为暴发确认和溯源检测提供实验室支持。方法对2005—2014年间分离自食品的91株Lm进行14个可变数目串联重复序列(Variable Number of Tandem Repeats,VNTR)位点的检测,评估最优检测位点组合并分析检测结果。结果通过采用软件分析,由LMV1、LMV2、LMV7、Lm10、Lm11、Lm23、LM-TR6、TR3和Lm15等9个VNTR位点组成的位点组合为最优MLVA检测位点,可以将91株Lm分离株分为70个型别,分型能力达到0.987 1。结论本研究建立的基于全自动毛细管电泳的由9个检测位点组成的Lm的MLVA分型方法,具有操作简便、快速、结果客观、操作标准化、易于在不同实验室间比较的优势,可作为一线检测方法用于李斯特菌病的暴发确认和溯源检测。展开更多
目的评价多位点可变数目串联重复序列分析(multiple-locus variable-number tandem-repeat analysis,MLVA)对福建地区宋内志贺菌的分型能力,为了解宋内志贺菌分子流行病学特征及疫情暴发时病原的溯源提供分析方法和基础数据。方法选择8...目的评价多位点可变数目串联重复序列分析(multiple-locus variable-number tandem-repeat analysis,MLVA)对福建地区宋内志贺菌的分型能力,为了解宋内志贺菌分子流行病学特征及疫情暴发时病原的溯源提供分析方法和基础数据。方法选择8个VNTR(Variable Number of Tandem Repeats)位点对68株临床分离株宋内志贺菌进行PCR扩增和毛细管电泳,利用BioNumerics软件进行聚类分析并构建最小生成树(Minimum spanning tree,MST),结合流行病学资料分析分型结果。结果 68株宋内志贺菌经MLVA分型后遗传关联度在20.647%~100%之间,按照100%的相似水平可分为66个MLVA型,呈遗传多态性,分辨系数为0.9986;有6个优势基因群(G1~G6),表现出时间地区聚集性。在最小生成树中,芗城分离株显示不同程度的亲缘关系,形成本土流行的优势克隆群;新罗分离株来源分散,存在少数优势基因簇。结论福建临床分离株宋内志贺菌具有基因多态性,MLVA方法对该菌有较好的分型能力,可用于研究菌株间的亲缘关系。展开更多
钩端螺旋体(钩体)病是一种自然疫源性疾病。近年来以可变数目串联重复序列(variable number of tand emrepeats,VYTR)为基础的分型方法,逐渐被应用于分子流行病学研究中。本研究选取我同致病性钩端螺旋体15群15型参考菌株,初步...钩端螺旋体(钩体)病是一种自然疫源性疾病。近年来以可变数目串联重复序列(variable number of tand emrepeats,VYTR)为基础的分型方法,逐渐被应用于分子流行病学研究中。本研究选取我同致病性钩端螺旋体15群15型参考菌株,初步探讨多位点可变数目串联重复序列分析(MLVA)在钩体病分子流行病学研究中的应用价值。展开更多
Background:The prevalence of human brucellosis in Qinghai Province of China has been increasing rapidly,with confirmed cases distributed across 31 counties.However,the epidemiology of brucellosis transmission has not ...Background:The prevalence of human brucellosis in Qinghai Province of China has been increasing rapidly,with confirmed cases distributed across 31 counties.However,the epidemiology of brucellosis transmission has not been fully elucidated.To characterize the infecting strains isolated from humans,multiple-locus variable-number tandem repeats analysis(MLVA)and whole-genome single-nucleotide polymorphism(SNP)-based approaches were employed.Methods:Strains were isolated from two males blood cultures that were confirmed Brucella m elitensis positive following biotyping and MLVA.Genomic DNA was extracted from these two strains,and whole-genome sequencing was performed.Next,SNP-based phylogenetic analysis was performed to compare the two strains to 94 B.melitensis strains(complete genome and draft genome)retrieved from online databases.Results:The two Brucella isolates were identified as B.melitensis biovar 3(QH2019001 and QH2019005)following conventional biotyping and were found to have differences in their variable number tandem repeats(VNTRs)using MLVA-16.Phylogenetic examination assigned the 96 strains to five genotype groups,with QH2019001 and QH2019005 assigned to the same group,but different subgroups.Moreover,the QH2019005 strain was assigned to a new subgenotype,llj,within genotype II.These findings were then combined to determine the geographic origin of the two Brucella strains.Conclusions:Utilizing a whole-genome SNP-based approach enabled differences between the two B.m elitensis strains to be more clearly resolved,and facilitated the elucidation of their different evolutionary histories.This approach also revealed that QH2019005 is a member of a new subgenotype(Hj)with an ancient origin in the eastern Mediterranean Sea.展开更多
文摘目的建立针对食品来源的单核细胞增生李斯特氏菌(Listeria monocytogenes,Lm)分离株的多位点串联重复序列分型(Multiple-Locus Variable number tandem repeat Analysis,MLVA)方法,为暴发确认和溯源检测提供实验室支持。方法对2005—2014年间分离自食品的91株Lm进行14个可变数目串联重复序列(Variable Number of Tandem Repeats,VNTR)位点的检测,评估最优检测位点组合并分析检测结果。结果通过采用软件分析,由LMV1、LMV2、LMV7、Lm10、Lm11、Lm23、LM-TR6、TR3和Lm15等9个VNTR位点组成的位点组合为最优MLVA检测位点,可以将91株Lm分离株分为70个型别,分型能力达到0.987 1。结论本研究建立的基于全自动毛细管电泳的由9个检测位点组成的Lm的MLVA分型方法,具有操作简便、快速、结果客观、操作标准化、易于在不同实验室间比较的优势,可作为一线检测方法用于李斯特菌病的暴发确认和溯源检测。
文摘目的掌握江苏省2018年人感染布鲁氏菌主要流行株的种型和基因型。方法运用普通PCR及AMOS多重PCR确认分离株的生物种型;采用多位点序列分型(Multilocus sequence analysis,MLSA)和多位点串联重复序列分析(Multiple-locus variable number tandem repeat analysis,MLVA)鉴定基因型,并与国内外流行株进行聚类分析。结果2018年共分离到56株布鲁氏菌,MLSA分型显示一株菌为猪种布鲁氏菌ST(Sequence type)17型,其他均为羊种布鲁氏菌ST8型。MLVA将56株菌分为47个基因亚型(46个羊种,1个猪种),聚类显示羊种布鲁氏菌全部为“东地中海簇”。结论2018年江苏省人感染布病主要为“东地中海簇”的ST8型羊种布鲁氏菌,并首次发现一例人感染ST17型猪种布鲁氏菌。
文摘目的评价多位点可变数目串联重复序列分析(multiple-locus variable-number tandem-repeat analysis,MLVA)对福建地区宋内志贺菌的分型能力,为了解宋内志贺菌分子流行病学特征及疫情暴发时病原的溯源提供分析方法和基础数据。方法选择8个VNTR(Variable Number of Tandem Repeats)位点对68株临床分离株宋内志贺菌进行PCR扩增和毛细管电泳,利用BioNumerics软件进行聚类分析并构建最小生成树(Minimum spanning tree,MST),结合流行病学资料分析分型结果。结果 68株宋内志贺菌经MLVA分型后遗传关联度在20.647%~100%之间,按照100%的相似水平可分为66个MLVA型,呈遗传多态性,分辨系数为0.9986;有6个优势基因群(G1~G6),表现出时间地区聚集性。在最小生成树中,芗城分离株显示不同程度的亲缘关系,形成本土流行的优势克隆群;新罗分离株来源分散,存在少数优势基因簇。结论福建临床分离株宋内志贺菌具有基因多态性,MLVA方法对该菌有较好的分型能力,可用于研究菌株间的亲缘关系。
文摘钩端螺旋体(钩体)病是一种自然疫源性疾病。近年来以可变数目串联重复序列(variable number of tand emrepeats,VYTR)为基础的分型方法,逐渐被应用于分子流行病学研究中。本研究选取我同致病性钩端螺旋体15群15型参考菌株,初步探讨多位点可变数目串联重复序列分析(MLVA)在钩体病分子流行病学研究中的应用价值。
基金supported by National Key R&D Program of China(Grant No.2020YFA0907101)Major Infectious Diseases such as AIDS and Viral Hepatitis Prevention and Control Technology Major Projects(2018ZX10201002)the National Natural Scientific Foundation of China(81860588).
文摘Background:The prevalence of human brucellosis in Qinghai Province of China has been increasing rapidly,with confirmed cases distributed across 31 counties.However,the epidemiology of brucellosis transmission has not been fully elucidated.To characterize the infecting strains isolated from humans,multiple-locus variable-number tandem repeats analysis(MLVA)and whole-genome single-nucleotide polymorphism(SNP)-based approaches were employed.Methods:Strains were isolated from two males blood cultures that were confirmed Brucella m elitensis positive following biotyping and MLVA.Genomic DNA was extracted from these two strains,and whole-genome sequencing was performed.Next,SNP-based phylogenetic analysis was performed to compare the two strains to 94 B.melitensis strains(complete genome and draft genome)retrieved from online databases.Results:The two Brucella isolates were identified as B.melitensis biovar 3(QH2019001 and QH2019005)following conventional biotyping and were found to have differences in their variable number tandem repeats(VNTRs)using MLVA-16.Phylogenetic examination assigned the 96 strains to five genotype groups,with QH2019001 and QH2019005 assigned to the same group,but different subgroups.Moreover,the QH2019005 strain was assigned to a new subgenotype,llj,within genotype II.These findings were then combined to determine the geographic origin of the two Brucella strains.Conclusions:Utilizing a whole-genome SNP-based approach enabled differences between the two B.m elitensis strains to be more clearly resolved,and facilitated the elucidation of their different evolutionary histories.This approach also revealed that QH2019005 is a member of a new subgenotype(Hj)with an ancient origin in the eastern Mediterranean Sea.