This preliminary report deals with the morphology of bacteria growing in biocoenosis with a diatomaceae Pinnularia. Electron micrographs of the mixed cultures showed the esistence of: (i) rod-shaped bacteria of usual type, (ii) typical caulobacteria (iii) thin filaments, and (iv) rod-shaped bacteria of usual dimenstions but filled with uniform spherical bodies about 0.1μ in diameter, which were arranged in a regular helical pattern. Significance of the last mentioned phenomenon was discussed suggesting the possibility either of a bacteriophagy or of some sort of cyclogeny, e. g. L-forms of bacteria, or the existence of a hitherto unknown submicrococcus.
1. From the cells of a strain of Lactobacillus casei, three kinds of lactic dehydrogenase were isolated. These are (i) a flavin-containing D-lactic dehydrogenase, (ii) a flavin-containing L-lactic dehydrognease and (iii) a DPN-linked D-lactic dehydrogenase. The former two were purified to almost homogeneous states. 2. These two enzyme showed, besides the difference in their substrate specificity, differences in their Km value, in their specificity towards electron acceptor and in their susceptivity towards atabrine. The prosthetic group of the D-enzyme was identified as FAD, while that of the L-enzyme was concluded to be some flavine nucleotide other than FAD. 3. Whereas the presence of a DPN-linked D-lactic dehydrogenase was confirmed beyond all doubt, no evidence whatsoever could be obtained for the existence of a DPN-linked L-enzyme. The absence of the latter enzyme was surprising in view of the fact that the bacterium used in the present study is a producer of L-lactic acid only. 4. The possible role of the flavin-containing L-lactic dehydrogenase in the L-lactic acid fermentation of this bacteria was discussed.
It was shown that the cells of Pediococcus cerevesiae (the so-called beer-sarcina), when grown in the presence of hop-resins and under anaerobic conditions in CO2-atmosphere, form giant cells having a diameter up to 15 microns. The giant cell contains chromatin-like bodies of various forms and is surrounded by a fragile cell wall stainable with tannic acid and crystal violet. Like the normal cells they are Gram-positive, but this property is lost when the cells are previously heated at 60° for 10 minutes.
Radioactive acetate, CH314COOH or 14CH3COOH, was incorporated into the molecule of variotin with a high yield, when introduced into the culture medium of Paecilomyces varioti. Active carbon atoms were localized in the C13-hydroxy acid moiety of variotin. Distribution of active carbon atoms in the molecule of variotin was suggested to be as follows: CH3COOH→ CH3-CH2-CH2-CH=C-CH=C-CH=CH-CH=CH-CONH-(CH2)3-COOCH3 OH CH3 CH3COOH→ CH3-CH2-CH2-CH=C-CH=C-CH=CH-CH=CH-CONH-(CH2)3-COOCH3 OH CH3
It was demonstrated that when methyl-radioactive L-methionine, 14CH3-SCH2CH2CH(NH2)COOH, was introduced into the culture medium of Paecilomycesvarioti, its methyl radical was incorporated into the molecule of variotin. The locus of the active carbon atom incorporated was shown to be the C-6-methyl carbon of the C13-hydroxy acid moiety of variotin. CH3SCH2CH2CH(NH2)COOH→ CH3-CH2-CH2-CH=C-CH=C-CH=CH-CH=CH-CONH-(CH2)3-COOCH3 OH CH3 The authors express a deep gratitude to Prof. HIROSHI YONEHARA and Dr. SETSUO TAKEUCHI for their kind assistance in this study. They are also indebted to Nippon Kayaku Co. for their cooperation in preparing the sample of cold variotin.
Regarding the collection of aerosol particles by fibrous filters, a semi-theoretical study was made on the correlation between single fiber efficiencies and operating variables. Discussions were made on the reasons why the log-penetration law cannot be generally applied to the design of air sterilization filters. It was pointed out that only an appropriate assess of the deviation from the law will lead to the successful design of the filters.
1. Quantitative measurement was made on the free nucleotides in the cells of Bacillus subtilis by subjecting the 32P-labeled cells to ion-exchange column and paper chromatographic analyses. 2.About 40 nucleotide derivatives were detected on paper chromoatograms, among which the following compounds were identified: AMP, CMP, GMP, UMP, ADP, UDP, UDPG and DPN. 3. The incubation with mitomycin C resulted in an increased concentration of total U.V.-absorbing substances, especially those of CMP, UMP, GMP, UDPAX and an unidentified adenine derivative. TMP, thymine and an unidentified UDP derivative were found to appear only in mitomycin treated cells.