• Journal of Microbiology and Biotechnology
• /
• 제18권2호
• /
• pp.194-198
• /
• 2008

A newly designed Cytophaga-Flavobacteria-specific 16S rRNA gene primer pair was employed to investigate the CF community structure in the Bering Sea, revealing a previously unknown and unexpected high CF diversity in this high latitude cold sea. In total, 56 clones were sequenced and 50 unique CF 16 rRNA gene fragments were obtained, clustering into 16 CF subgroups, including nine cosmopolitan subgroups, five psychrophilic subgroups, and two putatively autochthonous subgroups. The majority of sequences (82%) were closely related to uncultured CF species and could not be classified into known CF genera, indicating the presence of a large number of so-far uncultivated CF species in the Bering Sea.

• 한국환경과학회지
• /
• 제17권5호
• /
• pp.555-564
• /
• 2008

The bacterial community structure in biological activated carbon (BAC) process in drinking water treatment plant was investigated by Fluorescent in situ Hybridization (FISH) with rRNA-targeted oligonucleotide probe. Samples were collected at different three points in BAC process every month for one year. They were hybridized with a probe specific for the alpha, beta, gamma subclass of the class Proteobacteria, Cytophaga-Flavobacteria group and Gram-positive high G+C content (HGC) group. Total numbers of bacteria in BAC process counted by 4',6-diamidino-2-phenylindole (DAPI) staining were $5.4{\times}10^{10}$ (top), $4.0{\times}10^{10}$ (middle) and $2.8{\times}10^{10}$ cells/ml (bottom). The number of the culturable bacteria was from $1.0{\times}10^7$ to $3.6{\times}10^7$ cells/ml and the culturability was about 0.05%. The faction of bacteria detectable by FISH with the probe EUB338 was about 83% of DAPI counts. Gamma and alpha subclass of the class Proteobacteria were predominant in BAC process and their ratios were over 20% respectively. In top and middle, alpha, beta and gamma subclass of the class Proteobacteria competed with each other and their percentages was changed according to the season. In bottom, gamma subclass of the class Proteobacteria was predominant all through the year. It could be successfully observed the seasonal distribution of bacterial community in biological activated carbon process using FISH.