Rapid identification and enumeration of antibiotic resistant bacteria in urban canals by microcolony-fluorescence in situ hybridization
Rapid identification and enumeration of antibiotic resistant bacteria in urban canals by microcolony-fluorescence in situ hybridization
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DOI：
10.1248/jhs.52.703
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发表时间：
2006-12-01
影响因子：
--
通讯作者：
Nasu, Masao
中科院分区：
文献类型：
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作者：
Kenzaka, Takehiko;Yamaguchi, Nobuyasu;Nasu, Masao
采用微菌落法和荧光原位杂交（FISH）技术对泰国大都市曼谷运河中抗生素耐药菌的丰度和系统发育组成进行了研究。将细胞从水生样品直接捕获到聚碳酸酯膜上，并在含有抗生素的选择性琼脂上孵育24小时。使用具有rRNA靶向探针的FISH在过滤器上对单个抗生素抗性细菌小菌落样品进行分类。所有样品在含抗生素的选择性培养基上的微菌落形成单位（mCFU）数比菌落形成单位（CFU）数高0.5 ~ 8.1倍（平均3.4倍），且mCFU与CFU在所有样品中密切相关（r（2）= 0.89）。估计大肠杆菌（E。在非选择性培养基上，以rRNA为靶向探针的荧光原位杂交法检测到的大肠杆菌中，约有1%的细菌可被探针EUB 338检出。然而，它们约占微菌落形成诺氟沙星/四环素耐药菌中探针EUB 338可检测细菌的10%。在含有抗生素的选择性培养基上进行微菌落FISH将是一种有价值的工具，可以帮助获得有关水生环境中尚未培养的耐药细菌的数量和系统发育关系的信息。
The abundance and phylogenetic composition of antibiotic resistant bacteria in canals of metropolitan Bangkok, Thailand, were investigated using a microcolony method and fluorescence in situ hybridization (FISH). Cells were directly trapped from aquatic samples onto polycarbonate membranes and incubated for 24 hr on selective agar containing antibiotics. Individual antibiotic resistant bacterial microcolonies samples were classified on the filter using FISH with rRNA-targeted probes. The numbers of microcolony forming units (mCFU) on selective medium containing antibiotics were 0.5 to 8.1-fold (average, 3.4-fold) higher than those of colony forming units (CFU) in all samples, and mCFU and CFU closely correlated in all samples (r(2) = 0.89). Estimates of Escherichia coli (E. coli) determined by FISH with rRNA-targeted probe accounted for approximately 1% of bacteria detectable by probe EUB338 among microcolony-forming bacteria on nonselective medium. However, they accounted for approximately 10% of bacteria detectable by probe EUB338 among microcolony-forming norfloxacin/tetracycline-resistant bacteria. Microcolony-FISH on selective medium containing antibiotics would be a valuable tool that could help in obtaining information about the numbers and phylogenetic affiliations of yet-to be-cultured antibiotic-resistant bacteria in aquatic environments.