In situ detection of cell surface hydrophobicity of probe-defined bacteria in activated sludge
In situ detection of cell surface hydrophobicity of probe-defined bacteria in activated sludge
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DOI：
10.2166/wst.2001.0349
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发表时间：
2001-01-01
影响因子：
2.7
通讯作者：
Nielsen, PH
中科院分区：
文献类型：
--
作者：
Nielsen, JL;Mikkelsen, LH;Nielsen, PH
通过将具有特定表面特性的荧光微球粘附在细菌表面（mac法），在原位条件下研究了活性污泥中不同类型细菌的表面疏水性。该技术与rrna靶向寡核苷酸（FISH）荧光原位杂交技术相结合，可以直接在复杂系统中表征探针定义的细菌的表面特性，而无需事先富集或分离。这种MAC-FISH技术既可用于单个细菌，也可用于丝状细菌。在某工业污水处理厂的活性污泥中，两种丝状菌占主导地位。一种形态始终只吸引很少的疏水微球，表明细胞周围的外聚合物薄鞘具有亲水表面。利用一组分层的基因探针揭示了这些丝状体是硫化物氧化型硫喉虫，另一种主要的丝状体形态具有较厚的厚度。非常疏水的外聚合物鞘。这种丝状细菌被发现属于α -变形菌门。讨论了两种形态在底物吸收和逃逸形成方面的表面疏水性显著差异的相关性。
The surface hydrophobicity of different types of bacteria in activated sludge were investigated under in situ conditions by following the adhesion of fluorescent microspheres with defined surface properties to bacterial surfaces (the MAC-method). This technique was combined with identification of the bacteria with fluorescence in situ hybridization with rRNA-targeted oligonucleotides (FISH) and could thus be used for characterization of surface properties of probe-defined bacteria directly in a complex system without prior enrichment or isolation. This MAC-FISH technique could be used for single bacteria as well as filamentous bacteria. In the investigated activated sludge from an industrial wastewater treatment plant, two types of filamentous bacteria dominated. One morphotype consistently attracted only very few hydrophobic microspheres, indicating that the thin sheath of exopolymers around the cells had a hydrophilic surface. Use of a hierarchical set of gene probes revealed that these filaments were sulphide oxidising Thiothrix spp. The other predominating filamentous morphotype had a thick. very hydrophobic exopolymeric sheath. This filamentous bacterium was found to belong to the alpha-Proteobacteria. The relevance of the significant differences in surface hydrophobicity for the two morphotypes in respect to substrate uptake and flee formation is discussed.