The Influence Of Cyanophage’s Infection On Cell Cycle Protein In Microcystis

With the acceleration of urbanization and the rapid development of our agriculture and industry, domestic sewage, industrial wastewater, agricultural irrigation wastewater pollutant emissions increasing, coupled with weak awareness of environmental protection, eutrophication problems have become increasingly prominent, Cyanobacterial blooms phenomenon is getting worse of each river. Algal blooms threaten the quality and safety of the water system, so effective control and governance of the Algal blooms has important practical significance. Cyanophage is a virus capable of efficient decomposition of cyanobacteria, has important potential significance. on governance blue-green algae blooms.Screening a strain of Cyanophage which can infect Microcystis aeruginosa905from Taihu. To investigate the influences of viral infection on cell cycle of Microcystis aeruginosa905, we examined the changes of expression and activity of G2/M-phase cell cycle regulators in Microcystis aeruginosa905.By FeCl3chemical flocculation, ultrafiltration, PEG6000concentration methods to concentrate cyanophage. The results showed that FeCl3chemical flocculation concentrated cyanophage recovery was71.84%, concentrated by ultrafiltration recovery was67.65%, and PEG6000concentration method recovery was48.32%.By freeze-thaw, ultrasonic, grinding method to broken Microcystis aeruginosa905. The results showed that crushing efficiency by freeze-thaw method is not affected by cell density, while the crushing efficiency by ultrasonic and grinding methods increased slightly with the increasing of cell density. Crushing efficiency can reach above90%after freezing and thawing four times or ultrasonic8min, while after grinding8min cell disruption rate was around80%。By Microscopic count the number of algae cell and by double plate method count cyanophage plaques showed that due to the loss of Cyanophage inactivation efficacy of infection, the number of algal cells continued to grow in the control group, in Oh the number of algal cells was2.4×10个个/mL, after48h reaches5.5×106个/mL. While the experiment group, cyanophage continued to grow, from0h of6×10cells/mL to48h of1.92×106个/mL; in the beging of cyanophage infection, stimulate the growth of Microcystis aeruginosa905, but after18h the number of cyanophage was significantly decreased, from Oh of2.25x106cells/mL to48h of4.8x105cells/mL.Finally detected the change of p-Cdc25c, p34Cdc2, CyclinB proteins of Microcystis aeruginosa905by Western Blot. Western blot results showed that infection of Cyanophage stimulating the proliferation of Microcystis aeruginosa905and probably inhibited the expression of p34Cdc2, inhibit the activity of p34Cdc2/CyclinB complex, then block the life cycle of host cells at G2/M checkpoint.