12th International Conference on Harmful Algae

INTERNATIONAL SOCIETY FOR THE STUDY OF HARMFUL ALGAE12 th <strong>International</strong> <strong>Conference</strong> on Harmful Algae, Copenhagen, Denmark, 4-8 September 2006dot blot analysis of randomlyselected library clones. Thecomplete nucleotide sequence ofAT4-3 was determined by RACEmethod. BLAST homology searchshowed no similarity to any knowngenes or proteins. The predictedamino acid sequence of AT4-3 hasan N-terminal signal peptide forextracellular secretion, an N-linkedglycosylation site and eight cysteineresidues in half of the C-termini.Although the function of this gene isunknown, the results provide thefirst evidence of intracellularvariation between the differentmating-type cells in dinoflagellates.PO.09-08Occurrence of bacterial proteinthat reacts with specific antibodyagainst saxitoxinSession: PO.09 - Toxin synthesis andchemical structure of toxinsMassaki Kodama, Yoshinobu Takata,Shigeru SatoKitasato University, OFUNATO, JapanPreviously, we reported on theoccurrence of a saxitoxin-producingbacterium isolated fromAlexandrium tamarense cells, andwe suggested that PSP toxins of thedinoflagellate originate fromintracellular bacteria. However, thetoxin productivity of the bacteriumwas too small to explain the toxinamount of the dinoflagellate. Itsuggests that PSP toxins areintermediates of some bacterialsubstance. Recently, we have foundthat conjugates of toxins and thiolcompounds are formed bytransformation of 11-O-sulfatederivatives of STX such asgonyautoxin 1-4 to STXs. Thesefindings show that PSP toxins aremore reactive substances thanpreviously thought, and suggest thepossible occurrence of a bacterialsubstance bound to PSP toxins.Using the reaction of PSP toxinswith the thiol compound, the antigenin which STX is coupled with BSAwas prepared for the specificantibody that shows affinity to all thetoxin components examined. Thewestern blot analysis of the bacterialprotein extract using the antibodyagainst STX showed the presenceof bands. The hydrolyzate of theprotein also reacted with theantibody. These results suggest theoccurrence of proteins with PSPtoxin(s) as constituent(s).PO.04-01Growth of harmful blue-greenalgae after viable gut passage incrucian and silver carpSession: PO.04 – Food chainsVI Kolmakov 1 , MI Gladyshev 1 , OVAnishchenko 1 , SM Chuprov 2 , EAIvanova 3 , ES Kravchuk 1 , IV Zuyev 21 Institute of Biophysics of SB of RAS,KRASNOYARSK, Russia2 Krasnoyarsk State University,KRASNOYARSK, Russia3 Krasnoyarsk State AgriculturalUniversity,KRASNOYARSK, RussiaThe role of fish-gut passageenhancing harmful blue-green algaeproductivity has recently beenreported for a number of speciesresiding in eutrophic lakes. The aimof present work was experimentalstudy of growth of harmful bluegreenalgae after passage throughintestinal tract of crucian carp(Carassius auratus Linn.) and silvercarp (Hypophthalmichthys molitrixVal.). Growth of harmful algaepassed through the intestine ofcrucian and silver carp from smallSiberian reservoirs were comparedwith those of harmful algae takendirectly from the reservoirssubjected to blue-green algal206