Study on application of cyanobacterial vector

自养微浮游生物是一类影响生物地球化学过程并影响海洋和湖泊初级生产命运的微生物。为了了解噬藻体在沿海海洋环境中的生态作用及其对蓝藻繁殖和养分循环的影响，了解噬藻体的感染性及其与宿主海洋微浮游蓝藻之间的相互作用至关重要。本研究探讨了噬菌体作为分子生物技术载体的应用。本文分离到了一株新的毒力强的噬藻菌（S-KM1），并对其在鹿木神纳湾的季节性感染性进行了研究——富藻红蛋白聚球菌（KFM001）。我们发现，在秋季，噬菌体滴度从无法检测到到750000个细胞/ml不等，并在聚球菌秋季华开始约一周后开始增加。在秋季的几个月里，噬菌体数量以一种与宿主丰度轻微的方式振荡，显示出大约一周的滞后。我们从0算出来的。0055%对2。在秋季聚球菌爆发期间，每天有1%的宿主种群被噬菌体裂解。这表明，溶血性噬菌体在调节海洋舌球菌种群密度方面具有显著的作用。此外，我们还展示了它们的透射电镜阴性染色和噬菌体DNA的特征，以及我们的噬菌体与其他噬菌体的分子系统发育关系。作为分子生物技术的一种工具，我们探讨了这些噬菌体作为载体的应用。但是，由于噬菌体的宿主范围很窄，传染性不强，所以没有成功。噬菌体不具有保存的耐受能力。通过本研究发现，广泛的宿主范围、较强的传染性和耐保存能力是这些噬菌体作为载体应用的重要条件。

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.