Shitashiro Maiko, Kato Junichi, Fukumura Tsuyoshi, Kuroda Akio, Ikeda Tsukasa, Takiguchi Noboru, Ohtake Hisao
Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8530, Japan.
J Biotechnol. 2003 Feb 27;101(1):11-8. doi: 10.1016/s0168-1656(02)00285-7.
Bacterial aerotaxis (the movement of a cell toward oxygen) was evaluated for its potential use in detecting the toxicity of chemicals to microorganisms. The level of toxicity was determined by the concentration of test chemicals resulting in a 50% inhibition of aerotaxis of Pseudomonas aeruginosa PAO1 after 40 min of exposure. The aerotactic responses of P. aeruginosa were measured by using chemotaxis well chambers. Each clear acrylic chamber had a lower and upper well separated by a polycarbonate filter with a uniform pore size of 8.0 microm. To automatically detect bacterial cells that crossed the filter in response to a gradient of oxygen, P. aeruginosa PAO1 was marked with green fluorescent protein (GFP), and the GFP fluorescence intensity in the upper well was continuously monitored by using a fluorescence spectrometer. By using this technique, volatile chlorinated aliphatic compounds, including trichloroethylene (TCE), trichloroethane, and tetrachloroethylene, were found to be inhibitory to bacterial aerotaxis, suggesting their possible toxicity to microorganisms. We also examined more than 20 potential toxicants for their ability to inhibit the aerotaxis of P. aeruginosa. Based on these experimental results, we concluded that bacterial aerotaxis has potential for use as a fast and reliable indicator in assessing the toxicity of chemicals to microorganisms.
对细菌趋氧性（细胞向氧气的移动）用于检测化学物质对微生物的毒性的潜力进行了评估。毒性水平由测试化学物质的浓度决定，该浓度在暴露40分钟后导致铜绿假单胞菌PAO1的趋氧性受到50%的抑制。使用趋化性孔室测量铜绿假单胞菌的趋氧反应。每个透明丙烯酸室有一个上下孔，由孔径均匀为8.0微米的聚碳酸酯过滤器隔开。为了自动检测响应氧气梯度穿过过滤器的细菌细胞，用绿色荧光蛋白（GFP）标记铜绿假单胞菌PAO1，并使用荧光光谱仪连续监测上孔中GFP的荧光强度。通过使用该技术，发现包括三氯乙烯（TCE）、三氯乙烷和四氯乙烯在内的挥发性氯化脂肪族化合物对细菌趋氧性具有抑制作用，表明它们可能对微生物有毒性。我们还检测了20多种潜在毒物抑制铜绿假单胞菌趋氧性的能力。基于这些实验结果，我们得出结论，细菌趋氧性有潜力作为评估化学物质对微生物毒性的快速可靠指标。
