The seagrass Zostera marina harbors growth-inhibiting bacteria against the toxic dinoflagellate Alexandrium tamarense
The seagrass Zostera marina harbors growth-inhibiting bacteria against the toxic dinoflagellate Alexandrium tamarense
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DOI：
10.1007/s12562-013-0688-4
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发表时间：
2014-01
影响因子：
1.9
通讯作者：
Y. Onishi;Yuka Mohri;A. Tuji;K. Ohgi;A. Yamaguchi;I. Imai
中科院分区：
文献类型：
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作者：
Y. Onishi;Yuka Mohri;A. Tuji;K. Ohgi;A. Yamaguchi;I. Imai
海草具有化感作用，可以减少浮游植物的生长。从海带中筛选出两株对有毒甲藻塔玛亚历山大藻（Alexandrum tamarense）具有较强抑制活性的生长抑制菌E8和E9。即使初始接种量小至2.9 cells ml−1，菌株E9也能显著抑制塔玛曲霉的生长。该菌对赤潮藻Chattonella antiqua和Heterosigma akashiwo、甲藻Heterocapsa circulocapsa quama和角毛藻Chaetoceros mitra也有生长抑制作用。小亚基（SSU）核糖体DNA（rDNA）序列分析表明，这些菌株最有可能属于黄杆菌科（Flavobacteriaceae），并证明另一株抑菌株（E8）与菌株E9为同一种。从同一海草样品中分离出的两种菌落颜色不同的其他细菌菌株（E4-2和E10）没有显示出生长抑制活性。有趣的是，菌株E4-2显示与E8和E9相同的序列（100%），并且菌株E10以99.80%的相似性匹配E8和E9。海藻中的黄杆菌E8、E9等生长抑制细菌除了能抑制海藻的化感作用外，还能抑制有毒甲藻塔玛亚历山大藻（Alexandiumtamarense）对贝类的毒害。
Seagrasses are known to have allelopathic activity to reduce growth of phytoplankton. We found growth-inhibiting bacteria (strains E8 and E9) fromZostera marinapossessing strong activity against the toxic dinoflagellateAlexandrium tamarense. Strain E9 markedly inhibited growth ofA. tamarenseeven with initial inoculum size as small as 2.9 cells ml−1. This bacterium also had growth-inhibiting effects on the red-tide raphidophytesChattonella antiquaandHeterosigma akashiwo, the dinoflagellateHeterocapsa circularisquama, and the diatomChaetoceros mitra. Small subunit (SSU) ribosomal DNA (rDNA) sequencing analysis demonstrated that the most probable affiliation of these strains wasFlavobacteriaceae, and proved that another inhibitory bacterial strain (E8) was the same species as strain E9. Two other bacterial strains (E4-2 and E10), showing different colony color and isolated from the same seagrass sample, revealed no growth-inhibiting activity. Interestingly, strain E4-2 showed the same sequences as E8 and E9 (100 %), and strain E10 matched E8 and E9 with 99.80 % similarity. Growth-inhibiting bacteria against the toxic dinoflagellateAlexandrium tamarenseassociated with seagrass, such asFlavobacteriumspp. E8 and E9, are able to repress shellfish poisoning besides the allelopathic activity of seagrass itself.