Faculty of Science, Department of Biology, Section of Fundamental and Industrial Microbiology, Istanbul University, Vezneciler, 34134, Istanbul, Turkey.
Folia Microbiol (Praha). 2013 Sep;58(5):349-60. doi: 10.1007/s12223-012-0216-4. Epub 2012 Dec 19.
In this study, 99 Gram-negative rod bacteria were isolated from cooling tower water, and biofilm samples were examined for cell-to-cell signaling systems, N-acyl homoserine lactone (AHL) signal molecule types, and biofilm formation capacity. Four of 39 (10 %) strains isolated from water samples and 14 of 60 (23 %) strains isolated from biofilm samples were found to be producing a variety of AHL signal molecules. It was determined that the AHL signal molecule production ability and the biofilm formation capacity of sessile bacteria is higher than planktonic bacteria, and there was a statistically significant difference between the AHL signal molecule production of these two groups (p < 0.05). In addition, it was found that bacteria belonging to the same species isolated from cooling tower water and biofilm samples produced different types of AHL signal molecules and that there were different types of AHL signal molecules in an AHL extract of bacteria. In the present study, it was observed that different isolates of the same strains did not produce the same AHLs or did not produce AHL molecules, and bacteria known as AHL producers did not produce AHL. These findings suggest that detection of signal molecules in bacteria isolated from cooling towers may contribute to prevention of biofilm formation, elimination of communication among bacteria in water systems, and blockage of quorum-sensing controlled virulence of these bacteria.
在这项研究中，从冷却塔水中分离出了 99 株革兰氏阴性杆菌，并对生物膜样本进行了细胞间信号系统、N-酰基高丝氨酸内酯 (AHL) 信号分子类型和生物膜形成能力的检测。从水样中分离出的 39 株菌株中有 4 株（10%），从生物膜样本中分离出的 60 株菌株中有 14 株（23%）被发现能够产生各种 AHL 信号分子。研究结果表明，浮游菌的 AHL 信号分子产生能力和生物膜形成能力低于固着菌，且两组间的 AHL 信号分子产生能力有显著差异（p < 0.05）。此外，还发现从冷却塔水和生物膜样本中分离出的同一种细菌产生不同类型的 AHL 信号分子，而且细菌 AHL 提取物中也存在不同类型的 AHL 信号分子。在本研究中，观察到相同菌株的不同分离株并不产生相同的 AHLs 或不产生 AHL 分子，而且被认为是 AHL 产生菌的细菌也不产生 AHL。这些发现表明，对从冷却塔中分离出的细菌中的信号分子进行检测，可能有助于预防生物膜的形成，消除水中细菌之间的通讯，并阻断这些细菌群体感应控制的毒力。
