Microbiological environmental assessment in Southeast Asia

为保障东南亚地区水环境的安全，保证淡水的微生物质量，本研究项目在2005财年取得了研究成果。它由与细菌的16S rRNA相对应的寡核苷酸探针组成。该DNA芯片为我们提供了一种同时检测水环境中各种细菌的便捷方法。2.根据研究，细菌的生理状态可以通过荧光原位杂交结合活染色和gyrB基因mRNA的定量来评估。3.在湄公河沿岸的Kracheh(柬埔寨)和Can Tho(越南)采集的样品中，四环素耐药细菌的出现频率高于柬埔寨的Tonle Sape湖和越南的胡志明河口(越南)。在湄公河底泥中发现了多种四环素基因。4.铜绿微囊藻的胞外代谢产物促进了质粒的接合转移。

Objective of this research project is to assure microbiological quality of fresh water in order to keep safety of aquatic environment in Southeast Asia.Research results in FY20051.DNA microarray with newly designed probes was created. It consists of the oligonucleotide probes which corresponds to the 16S rRNA of bacteria. This DNA microarray provided us to obtain a convenient approach to detect various species of bacteria in aquatic environment simultaneously.2.According to the research, bacterial physiological states can be estimated by fluorescence in situ hybridization with vital staining and quantification of mRNA of gyrB gene.3.The frequencies of occurrence of tetracycline-resistant bacteria were higher in samples obtained at the sites in Kracheh (Cambodia) and Can Tho (Viet Nam) along the Mekong River than the sites in the lake Tonle Sape (Cambodia) and the Ho Chi Minh estuarine (Viet Nam). Various tetracycline genes were found in sediment of the Mekong River.4.The extracellular metabolic products by Microcystis aeruginosa enhanced conjugal transfer of plasmid.