Clarification of microscopic soil ecosystem of methane-producing bacteria and sulfate-reducing bacteria

众所周知，自然环境中甲烷气体的产生在很大程度上受产甲烷细菌和硫酸盐还原细菌之间的竞争控制。因此，本研究开发了一种新的荧光显微图像检测系统来阐明土壤中的甲烷竞争。从1995年4月到1996年3月，我们获得了以下结果：1)通过测定pH、Eh、甲烷产量、模型体系中S和有机物的浓度来阐明稻田土壤中甲烷产生菌的生态系统。2)利用荧光探针5-(和6-)磺基荧光素二乙酸酯和6-羧基荧光素乙酸乙酯-乙酰氧甲基-1-酯，建立了土壤中所有活细菌的可视化方法。在东京湾海边的人工土壤中，用荧光显微镜采集。4)产甲烷细菌的荧光光谱峰值分别为420 nm和460 nm。

It is well known that the methane gas production in natural environments is largely controlled by the competition between methane-producing bacteria and sulfate-reducing bacteria. Therefore, in this study we developed a new image-detection system by fluorometry and microscopy for clarifying this competition in soil.From April in 1995 through March in 1996 we obtained the following results : 1) Ecosystem of the methane producing-bacteria in paddy soil was clarified by measuring pH, Eh, methanegas production, and concentrations of S^<2-> and organic materials in model systems. 2) Two visualization methods for all living bacteria in soil were developed by using fluorescence probes, 5- (and 6-) sulfofluorescein diacetate and 6-carboxyfluoresceindiacetate acetoxymethy1 ester.3) Photographs of living methane-producing bacteria (Mathanosarcina sp.) in an artificial soil of the seaside of Tokyo Bay were taken by fluorescence microscopy. 4)Peaks of fluorescence spectra of the methane-producing bacteria were found to be 420nm and 460nm.