Coral degradation is a worldwide ecological problem. Bacterial diseases are a great danger to coral health. The pathogenic bacterium Vibrio alginolyticus XSBZ14 isolated from diseased coral had been identified as the pathogenic bacterium of Porites andrewsi White syndrome (PAWS) in Xisha Archipelago on transmission experiment. To date, the molecular mechanism by which this pathogen causes disease is unknown, and molecular diagnostics for diseases caused by this bacterium have not been developed. In an effort to restore damaged coral ecosystems in the South China Sea, efforts are underway to transplant flat-branch shore corals. There is therefore an urgent need to further develop specific and rapid detection methods for V. alginolyticus XSBZ14 in order to prevent this epidemic and ensure the successful implementation of compilation transplants. At first, a low sequence identity single-copy sequence S2 was selected from the genome by in-house Perl script. Using the designed specific primers, four different types of standard curves were subsequently plotted for the accurate quantification of the strain XSBZ14 in four different samples (DNA, bacterial suspension, coral tissue, seawater). Then, use the strain to infect the Galaxea fascicularis and test the strain in the coral culture water during the week. The rapid detection method of pathogenic bacteria by RT-PCR was established. The limit of detection (LOD) of the RT-PCR was 0.88 pg/reaction (0.44 pg/μL) in DNA, 2 CFU/reaction (1000 CFU/mL) in bacterial suspension, 2 CFU/reaction in coral tissue, and 20 CFU/reaction in seawater for the strain XSBZ14, respectively. In addition, according to the detection results of the RT-PCR, the strain XSBZ14 could survive in Galaxea fascicularis for a week, and the strain could also be detected from its reared seawater. These results indicated that the RT-PCR detection method of a coral pathogenic strain XSBZ14 was established. The method is a robust tool for the rapid detection and quantification of the coral pathogen, XSBZ14, and is very useful for PAWS epidemiological survey and specific pathogen-free coral transplantation in the South China Sea. And other coral species and their habitats might act as an important reservoir for the strain XSBZ14 and mediated its horizontal transmission in coral reefs.

中文翻译：

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新开发的RT-PCR方法定量检测溶藻弧菌菌株XSBZ14

珊瑚退化是一个世界性的生态问题。细菌性疾病对珊瑚健康构成巨大威胁。经传播实验，从病珊瑚中分离到的病原菌溶藻弧菌XSBZ14被鉴定为西沙群岛滨珊瑚(Porites andrewsi White Syndrome，PAWS)的病原菌。迄今为止，这种病原体引起疾病的分子机制尚不清楚，并且尚未开发出针对这种细菌引起的疾病的分子诊断方法。为了恢复南海受损的珊瑚生态系统，移植平枝海岸珊瑚的工作正在进行中。因此，迫切需要进一步开发针对溶藻弧菌XSBZ14的特异快速检测方法，以预防该流行病并确保编译移植的成功实施。首先，通过内部 Perl 脚本从基因组中选择低序列同一性单拷贝序列 S2。使用设计的特异性引物，随后绘制了四种不同类型的标准曲线，以准确定量四种不同样品（DNA、细菌悬浮液、珊瑚组织、海水）中的菌株 XSBZ14。然后，使用该菌株感染束状珊瑚，并在一周内在珊瑚培养水中测试该菌株。建立了RT-PCR快速检测病原菌的方法。RT-PCR 的检测限 (LOD) 在 DNA 中为 0.88 pg/反应 (0.44 pg/μL)，在细菌悬浮液中为 2 CFU/反应 (1000 CFU/mL)，在珊瑚组织中为 2 CFU/反应，以及 20分别针对菌株 XSBZ14 在海水中的 CFU/反应。另外，根据RT-PCR的检测结果，XSBZ14菌株可以在Galaxea fasciculis中存活一周，并且在其饲养的海水中也可以检测到该菌株。以上结果表明，建立了珊瑚致病菌株XSBZ14的RT-PCR检测方法。该方法是快速检测和定量珊瑚病原体XSBZ14的强大工具，对于PAWS流行病学调查和南海的无特定病原体珊瑚移植非常有用。其他珊瑚物种及其栖息地可能是 XSBZ14 菌株的重要储存库，并介导其在珊瑚礁中的水平传播。该方法是快速检测和定量珊瑚病原体XSBZ14的强大工具，对于PAWS流行病学调查和南海的无特定病原体珊瑚移植非常有用。其他珊瑚物种及其栖息地可能是 XSBZ14 菌株的重要储存库，并介导其在珊瑚礁中的水平传播。该方法是快速检测和定量珊瑚病原体XSBZ14的强大工具，对于PAWS流行病学调查和南海的无特定病原体珊瑚移植非常有用。其他珊瑚物种及其栖息地可能是 XSBZ14 菌株的重要储存库，并介导其在珊瑚礁中的水平传播。