Aeration during the early period of glucose dissimilation by resting cells of Lactobacillus buchneri IFO 3961 was found to induce succeeding anaerobic dissimilation of glucose, and it was confirmed that acetate, one of products in aerobic glucose dissimilation, is a compound which has the ability to induce anaerobic glucose dissimilation of this organism.
A comparative study of cyathin production by species and strains of the fungus Cyathus was made. Various haploid strains of C. helenae produced cyathin, though others produced no detectable amounts. The cyathin-producing strains, however, did not differ to any appreciable extent in the composition of the cyathin complex as shown by chromatographic analysis. Sectors of C. helenae produced different amounts of cyathin. All three species of Cyathus, C. africanus Brodie, C. helenae Brodie, and C. striatus (Huds.) wild. ex Pers., produced antimicrobial substances. Cyathus africanus is reported for the first time to possess biological activity.
An inosine-producing auxotroph of a Bacillus strain, which was insensitive to purine analogs such as 8-azaguanine and 8-azaxanthine, became sensitive when its adenine-deaminating activity was lost by mutation. From this "adenase-deficient" strain, a mutant resistant to 8-azaxanthine was isolated and it was found to accumulate xanthosine together with inosine. Then GMP reductase-deficient mutants were derived from the resistant strain; they accumulated guanosine, inosine, xanthosine, and the corresponding bases in the culture fluids. Further, two mutants, which were assumed to be partially deficient in purine nucleoside-hydrolyzing activity, were isolated from one of the GMP reductase-deficient mutants. These final mutants were found to accumulate a large amount of guanosine as a major product. Several culture conditions for guanosine production were also examined.
Oxidative phosphorylation in particulate fractions of eleven bacteria was examined without adding any soluble factor. The bacteria examined which could oxidize both NADH and succinate were divided from their properties of phosphorylation into the following three groups; (i) phosphorylation is scarcely coupled to the oxidation of both substrates, (ii) the P:O ratio in NADH oxidation is nearly equal to that in succinate oxidation, and (iii) the P:O ratio in NADH oxidation is lower than that in succinate oxidation. The bacteria whose P:O ratio in NADH oxidation is higher than that in succinate oxidation were not observed. In small particles of strains from group (ii) 0.1mM of cyanide inhibited NADH and succinate oxidation at a similar rate, while in small particles of strains from group (iii) cyanide inhibited succinate oxidation more strongly than NADH oxidation. These groups agree well with the groups classified by the quinones present. The bacteria in group (ii) contain benzoquinones alone or, at least, mainly, and those in group (iii) contain naphthoquinones alone. From these observations, the role of quinones in oxidative phosphorylation of bacterial particles was discussed.
Properties of COA-dependent aldehyde dehydrogenase and NAD-linked alcohol dehydrogenase of Leuconostoc mesenteroides IFO 3426 were studied, and it was found that the two dehydrogenases cannot be separated from each other, as well as from those of Escherichia coli B, by various methods of enzyme fractionation. It was also observed that the dehydrogenases of Leuconostoc mesenteroides appeared in a precipitate fraction prepared by centrifugation at 105, 000×g, and estimated to be associated with intracellular particles containing RNA.
Some organisms capable of lysing viable yeast cells were isolated from brewery sewage by the enrichment culture method by intermittent feeding with brewer's yeast. The strain (B 111-1) showing the highest lytic activity was identified as Arthrobacter luteus. The activity of Arthrobacter luteus, B 111-1, to lyse viable yeast cells appeared in the culture medium in the early stationary phase of the bacterial growth. The pattern of change in lytic activity during cultivation was different from those of β-1, 3-glucanase and protease activities suggesting that some additional factors are essential for the lysis of viable yeast cells. The pH value of culture medium during cultivation influenced the development of the activity considerably. The pH value first decreased and then increased with the appearance of lytic activity. The activity to lyse viable yeast cells developed adaptively when the organism was cultivated in a medium containing yeast cells or β-1, 3-glucan, suggesting that the latter causes induction. Cell-free culture fluid of the organism showed a lytic activity- on cells of brewer's yeast at all stages of growth and on viable cells of yeast strains belonging to a wide range of genera. However, it did not lyse viable cells of the yeasts Rhodoturula, Pichia, and Hansenula, or viable and heat-treated cells of bacteria and molds. The lytic activity of the cell-free culture fluid was not lost by dialysis. It was salted out at 0.395 saturation of ammonium sulfate and was lost on incubation at 60° for 5min. It was also inactivated by such protein denaturing agents as mercuric chloride, sodium laurylbenzene sulfonate, and silver nitrate, indicating that the lytic activity was due to enzymes. The optimum pH for lysis of viable yeast cells was 7.0-8.0. The lytic activity was relatively stable between pH 5 and 10.