• The seagrass Zostera marina harbors growth-inhibiting bacteria against the toxic dinoflagellate Alexandrium tamarense

Onishi, Yuka

Mohri, Yuka

Tuji, Akihiro

Ohgi, Kohei

Yamaguchi, Atsushi

Imai, Ichiro

    • The original publication is available at
  • Other Toxic blooms
  • Other Alexandrium tamarense
  • Other Algicidal bacteria
  • Other Seagrass
  • Other Zostera marina
  • Other Mitigation
  • Other Prevention
  • NDC 660
  • Seagrasses are known to have allelopathic activity to reduce growth of phytoplankton. We found growth-inhibiting bacteria (strains E8 and E9) from Zostera marina possessing strong activity against the toxic dinoflagellate Alexandrium tamarense. Strain E9 markedly inhibited growth of A. tamarense even with initial inoculum size as small as 2.9 cells ml(-1). This bacterium also had growth-inhibiting effects on the red-tide raphidophytes Chattonella antiqua and Heterosigma akashiwo, the dinoflagellate Heterocapsa circularisquama, and the diatom Chaetoceros mitra. Small subunit (SSU) ribosomal DNA (rDNA) sequencing analysis demonstrated that the most probable affiliation of these strains was Flavobacteriaceae, 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 dinoflagellate Alexandrium tamarense associated with seagrass, such as Flavobacterium spp. E8 and E9, are able to repress shellfish poisoning besides the allelopathic activity of seagrass itself.
PublisherSpringer Japan
Date Issued 2014-03
NIItypejournal article
Identifier URI
  • isIdenticalTo DOI
    • NCID AA10993718
    • ISSN 0919-9268
    • Fisheries Science
    80(2), 353-362