우리나라 동해안 유역으로부터 Ultramicrobacteria 의 분리 및 동정을 위한 연구

Abstract

Ultramicrobacteria(UMB) defined as cells having less than 0.1㎛3 of cell volume is highly abundant in most natural aquatic and terrestrial environment. In marine environment, only one strain has been isolated and studied, so we tried to discriminate UMB by growth potential at East-Sea of Korea. Microbial community structure between microbes remained on 0.2㎛-filter and those passing the pore(UMB) was compared for identify UMB. Clones from the sample affiliated into 4 major lineages, most of them revealed as uncultured alpha-proteobacteria. Gamma-proteobacteria showed predominant after 10weeks incubation. Microbes were cultivated by High Through-put Cultivation(HTC) method from the sample during incubation. At initial step of incubation, nearly 40 isolates detected among 192samples and they affiliated into 2 major lineage(alpha&gamma-proteobacteria). After 4weeks incubation, Pseudoalteromonas elyakovii become predominant under low nutrient condition. Under high nutrient condition cultivate belong to Actinobacteria&Bacteriodetes also detected. The acquired isolate not UMB, therefore, culture conditions well be diversified for the isolation of new UMB. [Supported by MEGRC]