Characterisation of the fluorescence from freshwater, planktonic bacteria
Characterisation of the fluorescence from freshwater, planktonic bacteria
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DOI：
10.1016/j.watres.2006.03.017
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发表时间：
2006-06-01
期刊：
影响因子：
12.8
通讯作者：
Baker, A.
中科院分区：
文献类型：
--
作者：
Elliott, S.;Lead, J. R.;Baker, A.
氨基酸类荧光已被用作废水流出物和天然沃茨中生物活性的指示剂，并且可以使用荧光光谱法检测。很少或没有工作能够最终说明这些所谓的“氨基酸样”荧光团与细菌活性导致的蛋白质相关。这项工作的目的是确定是否细菌是一个可能的原因，这些，氨基酸样的峰观察到在天然沃茨。此外，仅来源于一种细菌来源的荧光被确定为生长时间和温度的函数。铜绿假单胞菌分离自英国伯明翰市的城市河流驯服，并在无菌密封玻璃罐中在100 ml生长培养基中生长。细菌在11、25和37摄氏度下生长，最多10天。由样品的荧光分析生成3D激发-发射矩阵（EEM）图。在这些样品中观察到色氨酸和酪氨酸样荧光，类似于在天然和废水沃茨中观察到的荧光，表明文献中从水生系统观察到的荧光信号是生物来源的。从在不同温度下生长的细胞中获得荧光信号的显著差异。在2S和37 ℃下，发现细胞主要产生类Escherichan荧光，也检测到一些酪氨酸类荧光。还检测到另一种未知的荧光团（发射波长约为460 nm，在225、260和390 nm处有三个激发中心），可能是细菌产生的代谢物。在11摄氏度，在温带环境中，一个更现实的环境温度，定量和定性的差异，观察荧光信号相比，更高的温度，表明在更高的温度下进行的实验室观察可能不容易被用来解释环境过程。(c)2006爱思唯尔有限公司保留所有权利。
Amino acid-like fluorescence has been used as an indicator of biological activity in wastewater effluent and in natural waters, and can be detected using fluorescence spectroscopy. Little or no work has been able to state conclusively that these so called 'amino acid-like' fluorophores are associated with proteins present as a result of bacterial activity. This work aims to ascertain whether bacteria are one possible cause of these,amino acid-like' peaks observed in natural waters. In addition, fluorescence derived solely from one bacterial source was determined as a function of the growth time and temperature. The bacterium Pseudomonas aeruginosa was isolated from the urban River Tame, Birmingham, UK, and planktonic bacteria were grown in sterile, sealed glass jars, in 100ml growth media. Bacteria were grown at 11, 25 and 37 degrees C, over a maximum of 10 days. A 3D Excitation-Emission Matrix (EEM) plot was generated from fluorescence analysis of the samples. Both tryptophan and tyrosine-like fluorescence, resembling that observed in natural and waste waters, was observed in these samples, indicating that observed fluorescence signals from aquatic systems in the literature were of biotic origin. Significant differences in fluorescence signals were obtained from planktonic cells grown at different temperatures. At 2S and 37 degrees C, cells were found to produce predominantly tryptophan-like fluorescence, with some tyrosine-like fluorescence also detected. A further unknown fluorophore was also detected (emission wavelength of approximately 460 nm, with three excitation centres at 225, 260 and 390 nm), likely to be a bacterially produced metabolite. At 11 degrees C, a more environmentally realistic temperature in temperate environments, quantitative and qualitative differences were observed in fluorescence signals when compared with the higher temperatures, indicating that laboratory observations conducted at higher temperatures may not be easily used to interpret environmental processes. (c) 2006 Elsevier Ltd. All rights reserved.