CyanoHABs (cyanobacterial harmful algal blooms) are blooms of cyanobacteria capable of producing cyanotoxins, a large group of secondary metabolites that are toxic to most eukaryotes. In this work, the main aim was to evaluate the presence of multiple genes from each of the clusters responsible for biosynthesis of cyanotoxins (cylindrospermopsin, microcystin and saxitoxin) in total DNA obtained from sixteen environmental water samples by PCR. Microcystin gene mcyE was amplified in all analyzed samples. Among the cylindrospermopsin genes analyzed, only the cyrC gene was amplified from DNA obtained from three of sixteen samples. Of the three different saxitoxin genes analyzed, sxtB and sxtI were present in four and three of the sixteen samples studied, respectively, and sxtA did not show any positive result. Based on our results, we suggest caution when using only one gene from the full clusters responsible for biosynthesis of cyanotoxins, given that it may not be sufficient to confirm or exclude the toxigenic potential of a sample.

中文翻译：

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在富营养化水库（比林斯水库，巴西圣保罗）中检测产生蓝藻毒素的基因

CyanoHAB（蓝藻有害藻华）是能够产生蓝藻毒素的蓝藻藻华，蓝藻毒素是一大类对大多数真核生物有毒的次级代谢产物。在这项工作中，主要目的是通过 PCR 评估从 16 个环境水样中获得的总 DNA 中负责蓝藻毒素（圆柱藻毒素、微囊藻毒素和石房蛤毒素）生物合成的每个簇中是否存在多个基因。在所有分析的样品中都扩增了微囊藻毒素基因 mcyE。在分析的 cylindrospermopsin 基因中，只有 cyrC 基因从 16 个样本中的三个样本中获得的 DNA 扩增。在分析的三种不同的石房蛤毒素基因中，sxtB 和 sxtI 分别存在于所研究的 16 个样本中的四个和三个中，而 sxtA 未显示任何阳性结果。根据我们的结果，