[Objective]The aim was to measure gas vesicle in cyanobacteria and discuss its pretreatment methods.[Method]The capillary pressure method to determine gas vesicle in cyanobacteria was modified firstly,and then the low...[Objective]The aim was to measure gas vesicle in cyanobacteria and discuss its pretreatment methods.[Method]The capillary pressure method to determine gas vesicle in cyanobacteria was modified firstly,and then the lower detection limit and precision of modified apparatus were tested,finally the effects of two concentration methods and preservation methods on cell quantity and gas vesicle content of three cyanobacterias were studied.[Result]The lower detection limit and precision of modified apparatus to measure gas vesicle in three cyanobacterias were 0.001 8 μl/ml and 1% respectively.Unicellular Microcystis couldn＇t be concentrated effectively by filtration or centrifugation method,and the loss rate reached 50%.However,the colony of Microcystis and filamentous Planktothrix mougeotii could be effectively concentrated by centrifugation and filtration method respectively,with low loss rate.Besides,the effects of filtration and centrifugation on the content of gas vesicle in cells could be neglected.After preserved by direct refrigeration and adding Lugol＇s iodine solution for 7 d,there was no obvious change in cell concentration and gas vesicle content per cell,and the loss of gas vesicle under direct refrigeration was small,while the preservation of natural water samples should add Lugol＇s iodine solution.[Conclusion]The study could provide theoretical foundation for the researches on buoyancy regulation mechanism and blooming mechanism of cyanobacteria.展开更多
基金Supported by Chinese National Fundamental Research Program(973Program)(2008CB418105)~~
文摘[Objective]The aim was to measure gas vesicle in cyanobacteria and discuss its pretreatment methods.[Method]The capillary pressure method to determine gas vesicle in cyanobacteria was modified firstly,and then the lower detection limit and precision of modified apparatus were tested,finally the effects of two concentration methods and preservation methods on cell quantity and gas vesicle content of three cyanobacterias were studied.[Result]The lower detection limit and precision of modified apparatus to measure gas vesicle in three cyanobacterias were 0.001 8 μl/ml and 1% respectively.Unicellular Microcystis couldn＇t be concentrated effectively by filtration or centrifugation method,and the loss rate reached 50%.However,the colony of Microcystis and filamentous Planktothrix mougeotii could be effectively concentrated by centrifugation and filtration method respectively,with low loss rate.Besides,the effects of filtration and centrifugation on the content of gas vesicle in cells could be neglected.After preserved by direct refrigeration and adding Lugol＇s iodine solution for 7 d,there was no obvious change in cell concentration and gas vesicle content per cell,and the loss of gas vesicle under direct refrigeration was small,while the preservation of natural water samples should add Lugol＇s iodine solution.[Conclusion]The study could provide theoretical foundation for the researches on buoyancy regulation mechanism and blooming mechanism of cyanobacteria.
