Sugars contained in the blue-green alga, Tolypothrix tenuis, were extracted with 80% hot ethanol and purified. The combination of the charcoal-Celite colomn chromatography and paper chromatography was useful for the separation of two mono-, one di- and four oligosaccharides in the algal cells. The monosaccharides were identified as glucose and fructose and the disaccharide as sucrose. The oligosaccharides were considered to be a homologous series of glucofructan, consisting of glucose linked with increasing number of fructosyl units. The presence of such oligosaccharides could be demonstrated only in blue green algae but not in green algae so far tested.
The morphological growth cycle of Nocardia rubra was related to cellular composition when the organism was grown in a biphasic system for varying lengths of time up to 96hr. The DNA, RNA, lipid, protein, and ash content were determined. The morphology of the organism progressed from long branched filaments in the lag phase of the growth curve to shorter and shorter filaments with decreasing branching during the logarithmic phase. In the stationary phase the N. rubra cells were bacillary, and gradually became coccoid in the declining or death phase. The DNA percentage of the dry cell weight increased during the logarithmic growth phase from 2.2% to 3.0%, and then decreased to 1.5% during the stationary and declining phase. The RNA content was at a maximum of 20.1% in the middle of the logarithmic phase, declined sharply to 10% at the end of this phase, and then decreased more slowly to 4.0% in the declining phase. The lipid content increased rapidly from 9.9% to 20% in the early logarithmic period, at which point it leveled off and increased more gradually to 30.8% in the declining phase. The protein percentage of dry cell weight decreased from 50% to 43% during the early logarithmic period and remained steady throughout the remainder of the logarithmic and stationary phases, and finally decreased in the declining growth phase to 31%. The ash content increased steadily from 8.2% to 9.5% during the incubation period.
Comparative studies were carried out on the GC content of desoxyribonucleic acid isolated from cells of several species of lactic acid bacteria and Sporolactobacillus inulinus nov. sp.. The DNA of S. inulinus has a GC content similar to that of L. leichmannii and is far different from that of genus Clostridium.
The authors described the results of preliminary screenings of hydrocarbon-utilizing yeasts of which 56 strains were obtained. Fifty four strains belonging to the genus Candida: C. parapsilosis (26 strains), C. intermedia (9 strains), C. lipolytica (8 strains), C. tropicalis (5 strains), C. cloacae (1 strain), C. maltosa (1 strain), C. guilliermondii (1 strain), C. rugosa (1 strain), C. albicans (1 strain), and C. krusei (1 strain). The remaining two strains were Hansenula anomala and Rhodotorula rubra. All strains belonging to the genus Candida, except C. krusei, exhibited the powerful kerosene-utilizing ability. Stock cultures obtained from type culture collections also exhibited the strong kerosene-assimilatory ability as well as these newly isolated strains. n-Paraffins containing more than 9 carbon atoms were easily attacked by hydrocarbon-utilizing yeasts.
Forty-nine strains of kerosene-utilizing yeasts were taxonomically studied. All the strains except one belonged to the genus Candida, including the two new species. These were C. cloacae nov. sp. (1 strain), C. maltosa nov, sp. (1 strain), C. parapsilosis (26 strains), C. lipolytica (7 strains), C. tropicalis (3 strains), C. guilliermondii (1 strain), and C. intermedia (9 strains). The other one strain was Rhodotorula rubra. The descriptions of the new species were given.
The effect of surface active agents on the cell permeability of Micrococcus glutamicus for citrate was investigated. A marked effect of cetyl trimethyl ammonium bromide (CTAB) on the cell permeability was found. By the addition of 100μg of CTAB per 1mg of the dry cells, citrate could be converted theoretically to L-glutamate with the resting cells of M. glutamicus. Such a promoting action of surface active agents on cell permeability was almost proportional to its growth inhibitory activity. Similar effect was also observed in Proteus vulgaris, Torulautilis, baker's yeast as in M. glutamicus. Moreover, it was observed that corn steep liquor in the growing medium showed the strong inhibitory action on the elimination of cell wall barrier by the surface active agents. It may be probable to consider that some unknown factor(s) influencing the formation of the cell wall barrier is present in corn steep liquor.
Both strains K and M, belonging to B. subtilis, were found to possess 5′-nucleotide degrading activity. However, strain M was characterized by the fact that the formation of degrading enzyme(s) was well repressed by inorganic phosphate in contrast to strain K. The strong activity in strain C-30, an inosine producing mutant belonging to K, was suggested to be localized outside the cell membrane. A mutant MX-46, which was derived from a purine auxotroph belonging to M, showed no growth response to 0.2μmoles/ml of 5′-IMP and has nonspecifically lost 90% of the nucleotide degrading activity as well as alkaline phosphatase activity of the wild strain. On the other hand, alkaline phosphatase negative mutants derived independently from strain M still possessed 15-20% of nucleotide degrading activity of the wild strain. Therefore, it was concluded that MX-46 was different from normal alkaline phosphatase negative mutants. A pur+-transformant MT-16, derived from MX-46 via MX-97, accumulated four mononucleotides in the culture medium. An adenine requiring mutant, MX-7, derived from MT-16, did not accumulate IMP, and a try+-transductant MT-11 derived from MX-7, which had partially acquired the degrading activity, accumulated IMP together with hypoxanthine. The relationship between the bacterial degrading activity and the accumulation of nucleotide was discussed in view of these observations.
As a preliminary step of quantitative studies of the heterolactic fermentation system, standard conditions for steady rate fermentation were set up. Some basic aspects of the cytoplasm of Leuconostoc mesenteroides were studied under the defined conditions. These included dimension of the cytoplasm, internal pH, and concentration of several inorganic ions. Distribution and levels in the cells of NAD, NADP, thiamine pyrophosphate and CoA were also studied. Cytoplasmic levels of ATP and ADP were followed and found to be constant during fermentation.
Aspergillus niger grown on a synthetic medium containing sulfate as source of sulfur produced appreciably no protease, but if the sulfate was limmited in the medium, it produced protease actively irrespective of its poor growth. The optimum concentration of sulfate for the protease formation was 3×10-4M, whereas sulfate concentration supporting heavy growth of the fungus was 10-3M. By contrast, if the fungus was cultured in a complex medium containing peptone, the fungus produced protease actively irrespective of the high content of sulfur compounds. The formations of proteases in the sulfur-deficient synthetic medium and in the complex medium seemed to depend on different physiological activities of the hyphae, but these enzymes produced in the two media showed similar chromatographic pattern, i.e., at least two proteases were produced in both cases, although the relative amount of these proteases were different in both cases. The mode of formation of these different proteases by growing hyphae was discussed.