Isolation and characterization of a Cylindrospermopsis raciborskiistrain from Lake Xianghu,Hangzhou

摘要：

拟柱孢藻(Cylindrospermopsis)是一类具有固氮能力的丝状水华蓝藻,由于它可以产生拟柱孢藻毒素(Cylindrospermopsin,CYN)以及较强的入侵性,因此被广泛关注.在全球范围内,拟柱孢藻水华的暴发频率和范围显著增加.在中国,拟柱孢藻的分布呈现从东南沿海地区向内陆,从热带、亚热带向温带扩散的特点.目前国内仅发现两株产CYN藻株,均为2012年分离自杭州湘湖的藻株.2020年9月从杭州湘湖分离到一新拟柱孢藻藻株,经形态学特征鉴定为拉氏拟柱孢藻(Cylindrospermopsis raciborskii),基因测序表明该藻株和2012年分离自湘湖的一株有毒拟柱孢藻藻株的16S rRNA基因序列具有3个碱性的差异,和其他地区的拟柱孢藻的16S rRNA基因序列也表现出99.5%以上的相似性.通过对CYN合成基因片段的cyrA,cyrI和cyrJ的PCR检测,该藻株呈现阳性反应.经高效液相色谱(HPLC)化学检测,该藻株产CYN毒素,产毒量为1258.6μg/g.研究结果丰富了我国产CYN的藻株库,在一定程度上也表明其具有环境适应性和稳定性.研究再次验证了产CYN的拟柱孢藻的检测方法,包括DNA检测及HPLC化学检测.湘湖作为杭州萧山重要的饮用水备用水源,建议在今后的水环境监测和管理中引入拟柱孢藻和CYN监测.

Cylindrospermopsis is a filamentous cyanobacterial genus which can fix nitrogen and form water blooms.It has attracted more and more attention due to its ability to produce cylindrospermopsin(CYN)and its strong invasiveness.The frequency and scale of Cylindrospermopsis blooms are significantly increasing worldwide.In China,its distribution has also spread from the southeast coastal areas to inland regions,from tropical and subtropical to temperate zones.However,very few CYN producing Cylindrospermopsis strains were found in China,and only two strains were so far isolated from Lake Xianghu in Hangzhou in 2012.In this study,a new strain of Cylindrospermopsis raciborskii was successfully isolated from Lake Xianghu in September 2020.Morphological observation showed that it had a typical morphology within Cylindrospermopsis raciborskii.The 16S rRNA gene sequence of this strain was identical and three base pairs in difference respectively with the two strains of Cylindrospermopsis raciborskii isolated in 2012.The PCR detection on cyrA,cyrI and cyrJ showed that the strain was also positive to these three genes.Further chemical analysis by HPLC showed that the strain was capable of producing CYN toxin with a yield of 1258.6μg/g.This study increased the number of toxic Cylindrospermopsis strains in China,and also showed the adaptation and stability of Cylindrospermopsis species to a certain extent.The detection of CYN producing cyanobacteria,combining DNA detection and chemical detection by HPLC,has been applied again in this study.The methods and results of this study can suggest that Lake Xianghu,as an important drinking water source in Hangzhou,should introduce the detection of Cylindrospermopsis and CYN in water environmental and ecological monitoring in the future.The present study provides an important scientific basis and technical support for the monitoring of Cylindrospermopsis and its toxins.

作者：

晁爱敏 于海燕 肖鹏 李仁辉

Chao Aimin;Yu Haiyan;Xiao Peng;Li Renhui(Zhejiang Key Laboratory of Ecological and Environmental Monitoring,Forewarning and Quality Control,Zhejiang Environmental Monitoring Center,Hangzhou 310012,China;College of Life and Environmental Science,Wenzhou University,Wenzhou 325035,China)

机构地区：

浙江省环境监测中心浙江省生态环境监测预警及质控研究重点实验室 温州大学生命与环境科学学院

出处：

《betway官方app 学报：自然科学版》 CAS 北大核心 2021年第4期106-113,共8页

基金：

浙江省生态环境科研和成果推广项目(2020HT0007) 国家自然科学基金(31970219).

关键词：

拉氏拟柱孢藻 形态学特征 拟柱孢藻毒素 Cyr 蓝藻水华 湘湖

Cylindrospermopsis raciborskii morphological characteristics cylindrospermopsin Cyr cyanobacterial bloom Lake Xianghu

分类号：

X524 [环境科学与工程—环境工程]

杭州湘湖拉氏拟柱孢藻(Cylindrospermopsis raciborskii)藻株的分离及其特征研究.pdf