title: Virus-like particles suppress growth of the red-tide-forming marine dinoflagellate Gymnodinium mikimotoi.
abstract: We isolated 2 virus-like agents that suppressed growth of Gymnodinium mikimotoi from coastal waters of the Uwa Sea, Japan. The agents found in the flagellate cells, named GM6 and GM7, were filterable in a 0.22-microm-pore filter with approximately 100-nm shapes. Electron microscopic observation showed the presence of virus-like particles in severely damaged G. mikimotoi cells infected by GM6. The growth-suppression activity of the agents (GM6 or GM7) was lost by heating at 50 degrees C, with treatments of DNase and protease, and filtration through a 0.05-microm filter. Our results suggest that the agents are DNA viruses infectious to and virulent for G. mikimotoi. This is the first report of a virus-like agent specific to G. mikimotoi.
authors.affiliation: Center for Marine Environmental Studies, Ehime University, Matsuyama 790-8577, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Onji
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Nakano
authors.forename: Satoru
authors.initials: S
authors.lastname: Suzuki
mesh_terms: D000818:Animals; D004267:DNA Viruses / Q000378:metabolism / Q000472:pathogenicity* / Q000648:ultrastructure; D003851:Deoxyribonucleases / Q000378:metabolism; D004141:Dinoflagellida / Q000254:growth & development* / Q000648:ultrastructure / Q000821:virology*; D010450:Endopeptidases / Q000378:metabolism; D004986:Ether / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007564:Japan; D008854:Microscopy, Electron; D013696:Temperature
chemical_list: D004986:Ether; D003851:Deoxyribonucleases; D010450:Endopeptidases