Study on application of cyanobacterial vector

点击翻译按钮获取中文摘要

Autotrophic picoplankton are a group of microorganisms that affect biogeochemical processes and influence the fate of primary production in oceans and lakes. To understand the ecological role of cyanophage and its effect on blooming of cyanobacteria and nutrients cycling in the coastal marine environment, it is critical to understand cyanophage infectivity and the interactions that occur between the phage and its host marine cyanobacterial picoplankton. In this study, we examined to apply of cyanophage for a vector as a tool of molecular biotechnology.We isolated a new virulent cyanophage (strain S-KM1), and here have investigated its seasonal infectivity of cyanophage, phycoerythrin-rich Synechococcus sp. (strain KFM001) in Kagoshina Bay. We found that the phage titers ranged from undetectable to 750000 cells/ml in autumn, and began to increase about one week after the onset of the Synechococcus autumn bloom. During the autumn months, the phage numbers oscillated in a fashion that minored levels of host abundance, showing a lag of about one week. We calculated that from 0. 0055% to 2. 1% of the host population per day was lysed by the phage during a Synechococcus bloom in autumn. This suggests that lyic phages have a noticeable efect on regulating the densities of marine Svnechococcus populations.Also, we showed their transmission electron micrography of negative-stained and the characteristics of phage DNA and molecular phylogenetic relationship between our phage and others. As a tool of molecular biotechnology, we examined to application of those cyanophage for a vector. But, it is not succeed for the reason that the phage have a very narrow host range and not so strong infectivity. The phage do not have an tolerant capacity to preservation. It was found throug this study that wide host range, strong infectivity and tolerant capacity to preservation were important to application of those cyanophage for a vector.