The DNA content per mg (wet weight or dry weight) of cells of the genus Mycobacterium varied from strain to strain. It differed even within the same species. However, the DNA content appeared to be constant for each strain.
It seemed that the DNA content of the genus Mycobacterium tended to be a multiple of the amount found in the strain showing the least.
A parallelism between the DNA content and the complexity of the genetic response, in respect to drug resistance, has been discussed.

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1. Evidence has been presented that erythrocyte-sedimentation rates are influenced by lead blocks placed close to the tubes in which the red blood cells are sedimented.
2. The influence appears to be partly attributed to the elimination by the lead of a soft component capable of changing the sedimentation rates. In addition to this, some secondary component produced in the lead by a primary may be responsible for it.
3. The probable manner in which the secondary component may be produced in lead was discussed.

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The decreasing trend of survival rate after freeze-drying accompanied by an increase of culture days was studied comparatively with those of the malachitegreen-stainability and the recoverbility of bacterial cells on the BCG suspensions prepared from the pellicles grown on Sauton medium.
The results revealed that all of these phenomena, i.e., survival rate, malachitegreen stainability and recoverbility, showed similar decreasing trend expressed in the following formula as the function of culture days:Y=e^A-B√x (x≅culture day)From the high correlation between these decreasing curves, it will be possible to assume that the decrease it) the survival rate of BCG after freeze-drying in accordance with the increase of culture days is due to the weakened vitality of BCG cells in older culture ages.

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Mice of the CFW strain were more susceptible than the other strains of mice to the toxic effect of intravenously injected influenza virus (PR8 strain). Intravenous injection into the CFW mice with large amounts of fully infectious PR8 virus produced early haemorrhagic congestion in the lungs in addition to necrotic lesion in the liver and haemorrhage in the intestines. Histological study of the pulmonary lesion showed vascular engorgement, intra-alveolar haemorrhage, peribronchiolar and perivascular leucocyte infiltration, and bronchiolar and alveolar epithelial damage. It is hardly believable that this pulmonary lesion was the result of virus multiplication.
This early production of haemorrhagic congestion in the lungs of the CFW mice occurred also after intravenous injection of some toxic preparations having a markedly diminished or undetectable infectivity which were prepared by sonic disintegration of virus. In this case the pulmonary lesion was composed simply of vascular engorgement and intra-alveolar haemorrhage. However, on injection of the undiluted S fraction obtained from the sonically disrupted virus the pulmonary congestion was accompanied by moderate interstitial leucocyte infiltration.
From these histological findings it could be suggested that the production of bronchial and alveolar epithelial necrosis in the pulmonary lesion of theCFW mice depended upon the infective property of virus, the interstitial leucocyte infiltration upon the S antigen, and the interstitia capillary damage upon the toxic agent which is not responsible for infectivity and haemagglutination.

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Studies were made on the genetic analysis of cobalt-resistant mutant of E. coli K-12 isolated in the author's laboratory. In this report studies on the genetic transfer were described. The transfer experiments were performed either on a cobalt-containing synthetic agar or in a liquid medium supplemented with UV-induced cell-free lysate of the resistant mutant.
1. Cobalt resistance was transferred from the resistant strains to the sensitive strain of E. coli K-12, by streaking the donor and the recipient organisms parallel to each other on a cobalt-containing synthetic agar.
2. Resistance was also transferred from cobalt-resistant strains to sensitive strains of E. coli K-12 in an UV-irradiated cellular lysate. Resistance was not transferred to the E. coli B strain. Using the streptomycin-resistant strain of E. coli K-12 as the recipient, this organism became cobalt resistant and it also retained its streptomycin resistance.
3. The genetic transfer of cobalt resistance in E. coli K-12 was also accomplished from cobalt-resistant mutants, which became cobalt resistant according to the above transfer experiments, to sensitive strains of E. coli K-12, and this transferring activity is maintained even after 10 to 20 subcultures in cobalt free medium.
From these results it is evident that the genetic transfer of cobalt-resistance in E. coli K-12 was possible by the use of UV-induced cellular lysate. Presumably it may be transferred by vectors, namely phage particles, liberated from the donor cells. Precise studies on the nature of the transducing agent will be described in another publication.

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The therapeutic efficacy of antibiotics against the experimental tularemia in mice was studied analytically, and that
1. The infectious features in experimental tularemia employed in the present experiment nearly resembled those in human typhoid diseases.
2. Both dihydrostreptomycin and tetracycline were strikingly effective against tularemia and the treatment with chloramphenicol, kanamycin and erythromycin was progressively less effective.
3. In both cases of dihydrostreptomycin and tetracycline treatments that resulted in survival of 100% of the mice infected with B. tularense, the serum levels attained by the former treatment was approximately 10-times greater than the latter.
4. Dihydrostreptomycin was rapidly bactericidal against B. tularense in vitro at a high concentration, whereas it was bacteriostatic in the blood stream. On the other hand, tetracycline was bacteriostatic chiefly against the organisms both in vitro and in vivo.
5. In the dihydrostreptomycin treatment of tularemia, the pathogenic organisms were eradicated rapidly from the blood stream and spleen, whereas they persisted for a long period of time in the spleen when treated with tetracycline.
6. Dihydrostreptomycin treatment in the early stages of tularemic infection did not suppress the development of immunity.
7. In the course of infection-treatment of the mice infected with virulent B. tularense, immunity (host resistance) developed rapidly from the early stage of the infection.

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1. The growth of a strain of Streptococcus hemolyticus in semisynthetic media was reduced by using a ether-treated acid-hydrolysate of vitamin-free casein (vitamin-free Casamino acids-Difco) as the nitrogen source, but growth was recovered by the addition of the ether-extract of this hydrolysate.
2. It was determined that vitamin-free Casamino acids (Difco) contains 0.01-0.001% of stearic acid.
3. Stearic acid exerted an accelerative effect on Streptococcus hemolyticus strain S-8, most remarkably, while palmitic and arachidic acids affected to some extent. No accelerative action was observed on oleic, linoleic and linolenic acid, but inhibitory action was exerted by all of them in higher concentrations.

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Recently, many outbreaks of food poisoning due to raw meat of inshore fish have occurred in groups or sporadically in Japan. The occurrence of this food poisoning is limited to the summer season, and it is prevalent in the districts of seashore; however, there is no satisfactory data available as yet to explain the reason for these phenomena.
Some strains of Pseudomonas enteritis Takigawa (1956) have been presumed to be the causative bacteriae for the food poisoning of this type.
The authors made bacteriologic and epidemiologic studies of one group outbreak and twenty three sporadic cases of this type of food poisoning in a district along the Pacific Ocean. From the results of the studies, it was concluded that the strains of Pseudomonas enteritis (Takigawa) can cause enteritis in human beings after a heavy infection through foods. The symptoms of the disease resemble salmonellosis. These microorganisms belong to a kind of marine bacteria similar to Pseudomonas ichthiodermis ZoBelle, Vibris ichthyodermis Shewan and Pseudomonas formicans; however, this species is regarded as new, because it is resistant against bile and grow at 37°C. It is pathogenic for mammalia.

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The lipid A fractions were prepared from several bacterial species according to the method of Westphal with slight modifications. A remarkable similarity in their physicochemical properties was demonstrated.
The original lipid A fraction of E. coli consisted of ethersoluble materials (about 60 per cent), containing fatty acids, water soluble materials, containing glucosamine, unknown amino sugar, eight or more ninhydrin positive substances, presumably amino acids, and phosphoric acid.
The repeated intraperitoneal injections of the aqueous or oily suspension of the lipid A fraction showed a definite inhibitory effect against mouse Ehrlich ascites tumors, and about 40 to 60 per cent of the treated animals survived.
The repeated subcutaneous injections of the lipid A had no inhibitory effect on the development of tumor ascites.
Against the solid form of Sarcoma 37, the multiple intraperitoneal injections of lipid A also seem to exert some suppressive effects.Among the lipid A fractions used, at least, there were scarcely any differences in their antitumor effects.

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