Microbiological studies on the Yabase and Nishiyama oil-fields in Japan were carried out. The microflora of these oil-fields were more complicated than those of the Higashiyama oil-mining gallery where petroleum is recovered by mining. Considerable numbers of bacteria were found in the oil-brines of the oil-wells from about 700m in depth, but recognizable numbers of microorganisms were not found from depths of over 1, 000m. Pseudomonads were widely distributed in the samples obtained at these oil-fields, and hydrocarbon-utilizing bacteria, including methane-oxidizers, were found in the injection water of the waterflood, bottom water of oil-tanks, etc. Taxonomic studies of the isolated bacteria revealed that the species differed with the oil-producing district, even though the crude oil was produced from the same oil-zone. The microflora of the oil-brines were greatly different from those of the surface ground. From these facts, the use of bacterial tracers in petroleum mining was suggested.
Microbiological studies on the Niigata and Mobara gas-fields in Japan were carried out. A considerable number of aerobic bacteria, mainly belonging to genus Pseudomonas, were isolated from the gas-brines of a depth of 300m to 800m, but few or no microorganisms were found in depth over 1, 000m. Taxonomic studies revealed that a succession in the microflora took place in the gas wells during the three years from only a few microorganisms to a large number of pseudomonads of the fluorescent group. It was deduced from these facts that large amounts of fresh water may invade into the gas-layers from the outside, and that the water may flow from the north-east to the south-west in the Niigata gas-field. In comparison with the oil-brines, it was interesting that no kerosene-utilizing bacteria or anaerobic sulfate-reducers were found in the gas-brines in the Niigata gas-field. No microorganisms were found in the gas-brines in the Mobara gas-field. The use of bacterial tracers for natural gas mining, as well as for petroleum mining, is suggested.
Employing negative staining and thin sectioning techniques, the reduction sites of potassium tellurite and of tetrazolium salts in L. monocytogenes were revealed by electron microscopy. When the cells were negatively stained with phosphotungstate, the intracytoplasmic membrane system composed of complex lamellar and vesicular structures was distinctly demonstrated. Potassium tellurite was mainly reduced to metallic tellurium crystal on and/or near the inner layer of the cytoplasmic membrane but not in the intracytoplasmic membrane system. Triphenyl tetrazolium chloride (TTC) was reduced to TTC-formazan on or in the intracytoplasmic membrane system. As the TTC-formazan was dissolved in ethanol during the dehydration, the site of the formazan deposit appeared as a transparent crystal-like area surrounded by parts of the membrane system in sections of the cells. These findings strongly suggest that the tellurite-reduction system may principally be located on or near the inner layer of the cytoplasmic membrane, whereas the dehydrogenase system of the tetrazolium salt may be associated mainly with the intracytoplasmic membrane system.
Two methods for selection of mutagenic and phage inducing agents on plates have been described. The first method depends on the mutation of T2 phage from h+ to h; the mutation is detected by the appearance of plaques around the diffusion area of the sample. The second method is based on the liberation of λ phage from a lysogenic strain of E. coli; the induction is detected by the appearance of a turbid circle around the sample. The two methods are quite simple and directly applicable for selection of strains which produce mutagenic or phage inducing substances. Application of these methods as screening methods for selecting anti-tumor agents have also been discussed.
1) Succinate was not the activator for cellulase of Cellulomonas fimi strain R2, but the cellulase biosynthesis in the cells of this strain was stimulated by succinate. 2) In the aerobic culture in a synthetic medium, the effect of succinate on the growth and the cellulase formation were inhibited by fluoroacetate. 3) In the nutritionally rich medium, the stimulative effect of succinate was observed in both aerobically and anaerobically grown cells. 4) The results suggested that succinate affected the cellulase formation not only as the energy source through the tricarboxylic acid cycle, but also by another unknown way
1) Cellulase formation in Cellulomonas fimi R2 was stimulated when cells were cultured in media containing cellobiose or CMC. 2) Cells grown on glucose or starch media had no detectable cellulase; cellulase formation was stimulated by the addition of succinate. 3) Formation of cellulase by the stimulation of succinate was inhibited completely by chloramphenicol and strongly by 8-azaguanine, indicating that net protein synthesis was needed for this process. 4) The stimulatory effect of succinate was observed under both aerobic and anaerobic conditions, but in the latter a more pronounced effect resulted.
Using Candida rugosa JF 114, the differences between the monosaccharide components of kerosene-assimilated cells (K-cells) and those of glucose-assimilated cells (G-cells) were investigated. The monosaccharide components of both cells consisted of glucose, mannose and galactose. The K-cells have a lower content of total saccharide, namely, crude carbohydrate and a higher content of crude fat than the G-cells. It is concluded that there is no qualitative difference between the monosaccharide components of G-cells and K-cells.
Growth of E. coli strain D was inhibited by intermediates in the nucleic acid metabolism, of which purine derivatives such as hypoxanthine, inosine and adenosine were most active when singly added to the synthetic medium. Pyrimidine derivatives were also effective but very slightly in inhibiting cellular growth. 5-Amino-4-imidazole carboxamide was entirely inefficient. The inhibition induced by adenosine could be overcome by orotic acid, cytidine and NAD. Adenosine and inosine were converted by growing or resting cells of E. coli D to hypoxanthine which accumulated quantitatively in the medium.
(1) Dielectric behaviors of yeast suspensions containing both intact and "leaky" cells were investigated, with special regard to the all-or-none response of individual cells to HgCl2. (2) The data on the dielectric constants of Hg-treated samples were explained on the basis of the all-or-none response. (3) No definite dispersion curves of Hg-treated samples were obtained, but samples seemed to show a broader dispersion than that expected for a sample with a single critical frequency.