Blooms of microcystin-producing cyanobacteria are a problem worldwide. Microcystin is a liver hepatotoxin commonly found in bodies of water and is produced mainly by the genus Microcystis. The aim of the present study...Blooms of microcystin-producing cyanobacteria are a problem worldwide. Microcystin is a liver hepatotoxin commonly found in bodies of water and is produced mainly by the genus Microcystis. The aim of the present study was to develop and assess a competitive PCR method for the quantification of toxic and non-toxic Microcystis cells using the cpcBA and mcyB genes, which are respectively involved in the formation of phycocyanin and biosynthesis of microcystin. For the acquisition of competitor DNA, amplification sequences were carried out of the “cell DNA equivalent” of microcystin-producing (BCCUSP18) and non-microcystin-producing (BCCUSP03) strains of Microcystis spp. using primers described in the literature as well as others designed for the present study. The method was successfully developed, as competitor DNA was constructed and co-amplified with the target DNA. Competitive PCR proved to be useful in quantifying toxic and non-toxic cells of Microcystis spp. strains, representing a helpful methodology tool to study isolated toxin-producing cyanobacteria.展开更多
猫疱疹病毒I型(FHV-1)是威胁猫科动物健康的重要传染性疾病,本研究旨在研发一种灵敏、高效的FHV-1检测技术。依据GenBank上FHV-1 US6保守区域的基因序列,设计合成1对针对FHV-1 gD基因的引物,建立了一种SYBR Green I荧光定量PCR的检测方...猫疱疹病毒I型(FHV-1)是威胁猫科动物健康的重要传染性疾病,本研究旨在研发一种灵敏、高效的FHV-1检测技术。依据GenBank上FHV-1 US6保守区域的基因序列,设计合成1对针对FHV-1 gD基因的引物,建立了一种SYBR Green I荧光定量PCR的检测方法,构建标准曲线后分别验证该方法的特异性、敏感性、重复性,并将其进一步应用于人工感染猫产生的临床样本检测。结果:该特异性引物与猫杯状病毒(FCV)、猫细小病毒(FPV)和猫冠状病毒(FCoV)均未出现交叉反应,检测下限为14.78 copies/μL,组内和组间重复试验的变异系数均低于2%;该方法对临床样本的检出率比常规PCR高出25.46%;通过该方法检测人工感染FHV-1强毒后猫的每日排毒量,结果呈现上升趋势,与临床发病程度相符,猫的脏器病毒载量存在个体差异,但集中在心脏、肺脏、肠道和膀胱中检出。综上,该研究建立的SYBR Green I荧光定量PCR方法对FHV-1具有较好的特异性、灵敏度和重复性,为FHV-1感染的快速诊断以及疾病的防控提供方法支持。展开更多
基金supported by grants from“Fundacao de Amparoa Pesquisa do Estado de Sao Paulo”(Proc.2007/57672-0)CNPq(Proc.301739/2011-0)-Brazilian agencies for the promotion of Science.
文摘Blooms of microcystin-producing cyanobacteria are a problem worldwide. Microcystin is a liver hepatotoxin commonly found in bodies of water and is produced mainly by the genus Microcystis. The aim of the present study was to develop and assess a competitive PCR method for the quantification of toxic and non-toxic Microcystis cells using the cpcBA and mcyB genes, which are respectively involved in the formation of phycocyanin and biosynthesis of microcystin. For the acquisition of competitor DNA, amplification sequences were carried out of the “cell DNA equivalent” of microcystin-producing (BCCUSP18) and non-microcystin-producing (BCCUSP03) strains of Microcystis spp. using primers described in the literature as well as others designed for the present study. The method was successfully developed, as competitor DNA was constructed and co-amplified with the target DNA. Competitive PCR proved to be useful in quantifying toxic and non-toxic cells of Microcystis spp. strains, representing a helpful methodology tool to study isolated toxin-producing cyanobacteria.
文摘猫疱疹病毒I型(FHV-1)是威胁猫科动物健康的重要传染性疾病,本研究旨在研发一种灵敏、高效的FHV-1检测技术。依据GenBank上FHV-1 US6保守区域的基因序列,设计合成1对针对FHV-1 gD基因的引物,建立了一种SYBR Green I荧光定量PCR的检测方法,构建标准曲线后分别验证该方法的特异性、敏感性、重复性,并将其进一步应用于人工感染猫产生的临床样本检测。结果:该特异性引物与猫杯状病毒(FCV)、猫细小病毒(FPV)和猫冠状病毒(FCoV)均未出现交叉反应,检测下限为14.78 copies/μL,组内和组间重复试验的变异系数均低于2%;该方法对临床样本的检出率比常规PCR高出25.46%;通过该方法检测人工感染FHV-1强毒后猫的每日排毒量,结果呈现上升趋势,与临床发病程度相符,猫的脏器病毒载量存在个体差异,但集中在心脏、肺脏、肠道和膀胱中检出。综上,该研究建立的SYBR Green I荧光定量PCR方法对FHV-1具有较好的特异性、灵敏度和重复性,为FHV-1感染的快速诊断以及疾病的防控提供方法支持。
