Genetical ecology of microalgae causing Ciguatera in Taihiti

台希提岛雪卡毒素微藻的遗传生态学

基本信息

批准号：
05041095
负责人：
ISHIDA Yuzaburo
金额：
$ 4.8万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1993
资助国家：
日本
起止时间：
1993 至 1994
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-05041095/
关键词：
Ciguatera Toxic dinoflagellate benthic microalgae food poison Gambierdiscus coral reel Ciguatoxin Gambierdisucus

项目摘要

In many tropical coral reef regions, "ciguatera" has been known a human disease caused by the ingestion of toxic marine finfish. These toxins appear to originate from an epiphytic, benthic dinoflagellate found in ciguatera endemic areas of French Polynesia, Gambierdisucus toxicus. Chemical and toxicological studies of ciguatera toxins have been focused on G.toxicus, but there is little information about biological phase of this dinoflagellate. The present study sought to : 1. general survey of G.toxicus populations and distribution in Tahiti Island, 2. how G.toxicus and bacterial community attach to macroalga Jania (Rhodophyta) and interact each other, 3. to clarify the phylogenetic relationship and distinguish the population of G.toxicus. The results are as follows ;(1) A small bloom of G.toxicus priorly associated with Jania occurred from December to January in 1993-1994 in two fringing reef stations of Tahiti Island. G.toxicus cells localized even in the same station and the cell de … More nsity varied from 10-10^3 cells/g of wet algae. Most of G.toxicus cells usually swim in the Jania colony and attach temporary to the Jania branch with flagella. Some bacteria associated with Jania stimulate the growth of G.toxicus and possibly influence on G.toxicus occurrence.(2) Swimming of epiphytic dinoflagellate G.toxicus is stimulated by the extracellular substances from Jania. The stimulation activity on swimming of G.toxicus was also found in Galaxaura, Amphiroa, Corallina (Rhodophyta) and Halimeda (Chlorophyta) grwon in similar coral reef habitats.(3) The nucleotide sequences of 18SrRNA gene were determined from two strain of G.toxicus isolated from different stations in Tahiti Island to clarify their phylogenetic relationship in dinoflagellates. The result indicate that G.toxicus make a cluster with toxic Alexandrium causing paralytic shellfish poisoning and has a specific evolutionary position. It is suggested that at least three different populations are present in G.toxicus by restriction fragment length polymorphism analysis of rDNA inernal transcribed spacer and 5.8S regions. Less

在许多热带珊瑚礁区域中，由有毒的海洋鳍摄入的人类疾病是从附生的，底栖鞭毛藻的地方疾病这样的研究：1。大溪地岛的toxicus种群和分布的一般调查，2。2。随后;与1994年的1月，在大溪地岛的两个边缘礁石中发生了相关的Toxicus在Jania分支的Jania菌落中刺激了G.Toxicus的生长，可能会影响G.Toxicus的发生。在Galaxaura，Amphiroa，Corallina（Rhodophyta）和Halimeda（Chlorophyta）Grwon中发现的G.toxicus在类似的珊瑚礁栖息地中的游泳。澄清鞭毛的phy logenetic关系。