Tae Seok Ahn

Ecological development and genetic diversity of Microcystis aeruginosa from artificial reservoir in Russia.

Microcystis aeruginosa is a well-known Cyanobacterium responsible for the formation of toxic water blooms around the world. Shallow, warm, and eutrophic reservoirs provide the most favourable conditions for M. aeruginosa development. Numerous studies have been devoted to this species, but there still is a necessity to develop additional approaches for the monitoring of cyanobacteria in reservoirs. In this study, M. aeruginosa in the water column of a hypereutrophic Siberian reservoir was investigated by fluorescence, light, and electron microscopy as well as genetic analysis using a mcyE marker. Here, we demonstrate the genetic diversity and features of the fluorescence spectra for different ecotypes of this species. We suggest that a fluorescence approach can be used to identify M. aeruginosa in a natural environment in order to increase the effectiveness of ecological monitoring and water quality evaluation.

A new method for microbial cultivation and its application to bacterial community analysis in Buus Nuur, Mongolia

We performed a comparative analysis of bacterial diversity in a saline soda lake using a novel cultivation method termed the filter plate microbial trap method (FPMT), and conventional techniques together with DGGE (denaturing gradient gel electrophoresis). The new method allowed for cultivation of representatives of seven bacterial taxonomic groups, including seven novel species. This compares favorably to the results from cultivation of representatives of four taxonomic groups and only one novel species using standard approaches. Neither culture collection matched the community composition revealed by DGGE but the FPMT method produced a more representative collection of strains. We conclude that FPMT is a powerful device for improving bacterial culturability and narrowing the gap between microbial diversity in nature and cultivable microorganisms.