Collins C, Graham J, Brown L, Bresnan E, Lacaze J-P, Turrell E A
Fisheries Research Services, Marine Laboratory, PO Box 101, Victoria Road, Aberdeen, AB11 9DB, UK.
J Phycol. 2009 Jun;45(3):692-703. doi: 10.1111/j.1529-8817.2009.00678.x. Epub 2009 May 18.
Contamination of shellfish with paralytic shellfish poisoning (PSP) toxins produced by Alexandrium species poses a potential threat to the sustainability of the Scottish aquaculture industry. Routine LM analysis of water samples from around the Scottish coast has previously identified Alexandrium (Dinophyceae) as a regular part of the spring and summer phytoplankton communities in Scottish coastal waters. In this study, Alexandrium tamarense (M. Lebour) Balech isolated from sediment and water samples was established in laboratory culture. Species identification of these isolates was confirmed using thecal plate dissections and by molecular characterization based on their LSU and, in some cases, ITS rDNA sequence. Molecular characterization and phylogenetic analysis showed the presence of two ribotypes of A. tamarense: Group I (North American ribotype) and Group III (Western European ribotype). Assessment of PSP toxin production using hydrophilic interaction liquid chromatography-tandem mass spectrometry (HILIC-MS/MS) showed that A. tamarense Group I produced a complex array of toxins (∼2,000 fg STX equivalents · cell(-1) ) with the major toxins being C2, neosaxitoxin (NEO), saxitoxin (STX), gonyautoxin-4 (GTX-4), and GTX-3, while A. tamarense Group III did not produce toxins. Historically, it was considered that all Alexandrium species occurring in Scottish waters produce potent PSP toxins. This study has highlighted the presence of both PSP toxin-producing and benign species of A. tamarense and questions the ecological significance of this finding.
由亚历山大藻属产生的麻痹性贝类毒素污染贝类，对苏格兰水产养殖业的可持续发展构成了潜在威胁。此前，对苏格兰海岸周边水样进行的常规光学显微镜分析已将亚历山大藻（甲藻纲）鉴定为苏格兰沿海水域春季和夏季浮游植物群落的常见组成部分。在本研究中，从沉积物和水样中分离出的塔玛亚历山大藻（M. Lebour）Balech在实验室中进行了培养。通过壳板解剖以及基于其大亚基核糖体RNA（LSU），在某些情况下还基于内部转录间隔区（ITS）核糖体DNA序列的分子特征分析，对这些分离株进行了物种鉴定。分子特征分析和系统发育分析表明，塔玛亚历山大藻存在两种核糖体类型：第一组（北美核糖体类型）和第三组（西欧核糖体类型）。使用亲水相互作用液相色谱 - 串联质谱法（HILIC-MS/MS）对麻痹性贝类毒素产生情况进行评估，结果显示第一组塔玛亚历山大藻产生一系列复杂的毒素（约2000 fg石房蛤毒素当量·细胞⁻¹），主要毒素为C2、新石房蛤毒素（NEO）、石房蛤毒素（STX）、膝沟藻毒素 - 4（GTX - 4）和GTX - 3，而第三组塔玛亚历山大藻不产生毒素。从历史上看，人们认为在苏格兰水域出现的所有亚历山大藻物种都会产生强效的麻痹性贝类毒素。这项研究突出了产麻痹性贝类毒素和无害的塔玛亚历山大藻物种的存在，并对这一发现的生态意义提出了质疑。
