Studies on the Bacterial Metabolism by Means of Oxidation-Reduction Potential Ⅱ: The Fall of Potential and the Depth in Culture Media

Using Salmonella typhi 57S and Staphylococcns aureus (Terashima) as the test organisms, the author measured the fall of potential in the upper, midle and lower layers of salt solution media. The results are summarized as follows: 1) In the culture media of Sal. typhi 57S containing 10(-2)M glucose, the potential fall in each layer is a few times greater than that in the media without any substrate. This phenomenon is more marked in the media containing 200 mg bacteria than in those containing 100 or 150 mg. 2) In the media containing pyruvate, lactate or succinate, the fall of potential is greater in the upper layer, namely in an aerobic part, with the exception of the media of Staph. aureus containing succinate as its substrate. 3) In the upper and middle layers of the culture media of Sal. tvphi containing glutamate as its substrate, asparagine was proved paper-chromatographically. In the lower layer, asparagine could not be proved, and there was observed the fall of integration potential about 2.2 times that in the upper and middle layers. 4) In the culture media of Sal. typhi containing 10(-2)M glucose and alanine, glutamate was paper-chromatographically proved in all of the upper, middle and lower layers, and the fall of integration potential in the middle and lower layers was 2.2 to 2.5 times greater than that in the upper layer. In the combined administrations of glucose and other amino acids than alanine, the fall of integration potential in the middle and lowe layers was never beyond 1.6 times of that in the upper layer