Evaluation of sxtA and rDNA qPCR assays through monitoring of an inshore bloom of Alexandrium catenella Group 1
Evaluation of sxtA and rDNA qPCR assays through monitoring of an inshore bloom of Alexandrium catenella Group 1
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DOI：
10.1038/s41598-019-51074-3
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发表时间：
2019-10
影响因子：
4.6
通讯作者：
S. Murray;Rendy Ruvindy;G. S. Kohli;D. Anderson;M. Brosnahan
中科院分区：
文献类型：
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作者：
S. Murray;Rendy Ruvindy;G. S. Kohli;D. Anderson;M. Brosnahan
Alexandrum catenella（原A. tamarenseGroup 1，或A. fundyense）是北美和南美、欧洲、非洲、澳大利亚和亚洲麻痹性贝类中毒的主要原因。链甲藻xtA基因是参与麻痹性贝类毒素合成的一个基因，它的定量可能是一种有前途的方法，但还没有在链甲藻水华中进行评估。catenella，其中细胞丰度可能从检测不到到106个细胞L-1的数量级不等。在这项研究中，我们比较了dsxtA检测的性能，以qPCR检测靶向核糖体DNA（rDNA）的物种特异性区域和建立荧光原位杂交（FISH）显微镜方法。Passing-Bablok回归分析显示，当<5个细胞当量A时，xtA测定高估了丰度。分析了链霉菌DNA，但在其他方面比rDNA测定法更接近显微镜估计值，rDNA测定法在分析的整个浓度范围内高估了丰度，表明水华群体和用于测定校准的培养物之间的拷贝数差异。相比之下，xtA试验表现得更一致，表明拷贝数变异更少。xtA测定法是一种可靠、快速、有效的A定量方法。catenellaand对贝类PST污染具有预测作用。
Alexandrium catenella(formerlyA. tamarenseGroup 1, orA. fundyense) is the leading cause of Paralytic Shellfish Poisoning in North and South America, Europe, Africa, Australia and Asia. The quantification ofA.catenellaviasxtA, a gene involved in Paralytic Shellfish Toxin synthesis, may be a promising approach, but has not been evaluatedin situon blooms ofA. catenella, in which cell abundances may vary from not detectable to in the order of 106cells L−1. In this study, we comparedsxtAassay performance to a qPCR assay targeted to a species-specific region of ribosomal DNA (rDNA) and an established fluorescentin situhybridization (FISH) microscopy method. Passing-Bablok regression analyses revealed thesxtAassay to overestimate abundances when <5 cell equivalentsA. catenellaDNA were analysed, but otherwise was closer to microscopy estimates than the rDNA assay, which overestimated abundance across the full range of concentrations analysed, indicative of a copy number difference between the bloom population and a culture used for assay calibrationa priori. In contrast, thesxtAassay performed more consistently, indicating less copy number variation. ThesxtAassay was generally reliable, fast and effective in quantifyingA. catenellaand was predictive of PST contamination of shellfish.