Isolation And Characterization Of Three Kinds Of Algicidal Microorganism

This article using the red-tide algae as the material, taking water samples from Xiangshan harbour, the East China Sea; then concentrated by backflushing ultrafiltration, and then to infect algae cells, finally we isolated a novel virus of Chaetoceros muelleri for the first time, and establish a stable system of Phycoviruses-Host of algae. After inoculation the virus 96h's later,it appears the phenomenon that the algae cell's culture becomes from dark brown to clarification, optical microscope showed most of the cells were ruptured and dead. The virus was purified via the methods of the saccharose gradient ultracentrifugation and Most-Probable-Number, electron microscopic analysis revealed that the viral capsid has a distinct icosahedral shape with a diameter of 58nm;its genome is about 23kb via molecular characterization. The virus has no reported in the world by now, it's a novel phycovirus.From natural waters concentrated by backflushing ultrafiltration, a novel virus named WH-1 that infects and lyses Chlorella Vulgaris Beij was isolated by repeated plaque isolation. After inoculation the virus 96h's later,it appears the phenomenon that the algae cell's culture becomes from green to yellow. Electron microscopic analysis revealed that the viral capsid has a distinct icosahedral shape with a diameter of 21nm. The plaque assay showed that the average diameter of plaques was about 3 mm after 64h. Since the virus WH-1 has an obvious discrepancy to the viruses that had isolated and reported in the world, it is a novel Chlorella virus worthy to study.Meanwhile,using the eukaryon water bloom algaes as the material, concentrated samples from natural water,and then to infect the algae cells,isolated an algicidal bacteria which can lyse Cyclotella meneghiniana kutz finally; after inoculation the bacteria 48h's later,it appears the phenomenon; the bacteria was purified via the methods of Most-Probable-Number and ultracentrifugation, and electron microscopic analysis revealed that it is bacilliform,about 0.552um×0.826um～0.57um×2.587um, the surface of the thalli is smooth, and the specific characters is to be further identified.