Showing papers in "Japanese Journal of Microbiology in 1969"

Ibaraki virus, an agent of epizootic disease of cattle resembling bluetongue. I. Epidemiologic, clinical and pathologic observations and experimental transmission to calves.

Abstract: Ibaraki virus multiplied and induced cytopathic effects in primary cell cultures of bovine, sheep and hamster kidney and chick embryo, and cultures of BHK21-WI2 cells of baby hamster kidney origin and mouse fibroblastic L cells, but did not in primary cultures of horse and swine kidney cells and HeLa cell cultures. The virus was readily passaged serially in 4 to 5-day-old eggs using the yolk sac inoculation and incubation at 33.5 C. The viral growth was better in eggs incubated at 33.5 C than 37 C, and in younger eggs, with high yields in yolk, yolk sac and embryo. The virus was passaged serially in newborn mice by the intracerebral route. The virus multiplied in the brain of mice of any age, but younger mice supported better viral growth and developed encephalitis. As the age of mice increased, the morbidity and mortality became lower, no deaths being observed in 2 to 3-week-old mice. These observations in cell cultures, embryonated eggs and mice emphasize the similarity of Ibaraki virus to bluetongue virus. No evidence was obtained that young adult rabbits and weanling guinea pigs are susceptible to Ibaraki virus. The virus seemed to have little if any pathogenicity but infectivity of a low grade for sheep, while the virus is capable of inducing clinical illness, even severe in some instances, in cattle. This is in contrast to bluetongue virus which is highly pathogenic for sheep and much less so for cattle. Serial passages in embryonated eggs and suckling mice resulted in attenuation for cattle of Ibaraki virus.

Distribution of R factors among Shigella strains isolated in Japan (II).

Abstract: Shigella strains isolated in Japan from 1968 through 1970 were surveyed for drug resistance and distribution of R factors. Of the 2688 strains, 93.4% were resistant to either one or various combinations of four drugs, tetracycline (TC), chloramphenicol (CM), streptomycin (SM) and sulfanilamide (SA). Among these resistant strains, 74.2, 10.7, 1.48, and 13.6% were quadruply, triply, doubly, and singly resistant, respectively. Fifty-eight per cent of these resistant strains were found to carry R factors when judged by transferability of the resistance. The isolation frequencies of R (TC. CM. SM. SA), R (CM. SM. SA), R (SM. SA), and R (TC. SM. SA) factors were 73.2, 13.0, 11.5, and 1.3%, respectively. The strains resistant to drugs other than the aforementioned four were very few; 4.3, 3.4, and 0.7% being resistant to ampicillin (APC), nalidixic acid (NA), and kanamycin (KM), respectively. Among 117 APC-resistant strains, 97.4% could transfer their APC resistance together with other resistance markers. Seventeen out of 18 KM-resistant strains could transfer KM resistance by mixed culture. But none of the NA-resistant strains could transfer their NA resistance. The authors could demonstrate strains carrying two different R factors in a cell and one of them was consistently an R (SM. SA) factor. These results were very similar to those obtained in surveys of strains isolated from 1965 through 1967.

Establishment of Candida albicans in the alimentary tract of the germ-free mice and antagonism with Escherichia coli after oral inoculation

Abstract: To solve the problems of the multiplication and invasion of Candida albicans in the alimentary tract, germ-free mice were orally inoculated with C. albicans and the antagonistic effect of superinfection with Escherichia coli was examined. C. albicans could easily be established in the alimentary tract of germ-free mice by inoculation with less than 10 organisms, whereas in the alimentary tract of the SPF mice, having normal bacterial flora, C. albicans could not establish even after inoculation with an overwhelming dose. In germ-free mice large numbers of the inoculated Candida were excreted in the feces throughout the observation period of 130 days, without affecting the conditions of the mice. By histopathological examination of these mice only one mouse showed microabscesses with leukocytic infiltration accompanied by hyperkeratosis and acanthosis in the epithelium of the forestomach. However even in this mouse no invasion of Candida cells into the acanthotic squamous cell layer was seen. After inoculation of the mice who had already E. coli in their gut as a monocontaminant with C. albicans, or even after inoculation of E. coli to the mice harboring Candida as a monocontaminant, E. coli always outnumbered C. albicans. In the former case Candida were even completely eliminated from the mice within few days. Thus, it appeared that in the alimentary tract of the mice, E. coli have the capacity to antagonize to C. albicans.

Immunochemical and Biochemical Studies of Fungi

Abstract: Polysaccharides were separated from mycelia and culture filtrates of the filamentous fungi Aspergillus niger and Penicillium chrysogenum, and purified by column chromatography on Sephadex G-50, DEAE- and CM-cellulose, successively. No nitrogen and phosphorus were detected in the polymer, and the sugar components were observed to be galactose and mannose. The polysaccharides were confirmed to be galactomannans which were easily hydrolyzed by weak acid, liberating galactofuranose and oligosugar in dialyzable fractions.

Titration and extensive serial passages of Yaba virus in vitro

Abstract: A sensitive assay system of Yaba virus (YV) was established in a cynomolgus monkey kidney cell line, JINET, in which the virus caused multilayered cellular foci countable even with the unaided eye. The specificity of the foci induced by YV in these cells was demonstrated by (1) the focus-forming ability was destroyed by heating at 60 C for 12 min; (2) the focus formation was inhibited by specific antiserum; (3) specific fluorescence was detected only in cells composing the foci when tested by fluorescent antibody technique; (4) a linear relationship was observed between the virus concentration and the number of foci formed; (5) YV preparation passed 20 times in JINET cells still possessed “tumorigenicity” in cynomolgus monkeys. The sensitivity of JINET cells to YV was comparable to that of cynomolgus monkeys, and YV was successively propagated in JINET cells with 2 log increase in infectivity titer during over 40 serial passages. Application of this assay system to growth kinetic studies of YV and quantitation of neutralizing antibody to YV is also discussed.

Heat‐Labile Toxin of Bordetella Pertussis Purified by Preparative Acrylamide Gel Electrophoresis

Abstract: The heat-labile toxin (HLT) of Bordetella pertussis was purified by column chromatography on DEAE-cellulose, salt fractionation and preparative acrylamide gel electrophoresis. The toxin obtained was confirmed to be free from hemagglutinins, protective antigens, histamin sensitizing factors, and K and O agglutinogens, and was shown to be homogenous by agar gel diffusion tests, ultracentrifugation, and electrophoresis. The minimal necrotic dose of the HLT in guinea pig was 0.01 μg dry weight. It was a protein in nature, contained a sugar moiety and possessed S value of 1.4. The toxicity of purified HLT was increased by mixing with a protein, such as rabbit serum.

Isolation and Properties of Two New RNA Phages SP and FI

Abstract: New RNA phages were isolated from feces of Siamang Gibbon and infants, and their characters were investigated. These phages, SP and FI were serologically unrelated to any of known RNA phages (group I, II and III) and were classified into groups IV and V. Several other characters, such as filtration and elution patterns through membrane filters, buoyant densities in CsCl, and UV sensitivities of SP and FI were similar to those of the group III phages, suggesting that a certain similarity between group III and IV or V might exist. Peculiar phage-host relations found in phages of FI group were also discussed. From these results, we propose new possible schemata for the grouping of RNA phages.

Rapid gas chromatographic analysis of microbial volatile metabolites.

Abstract: A direct injection of various culture supernatants into a column of Porapak Q was investigated as a rapid and simple technique for gas chromatographic analysis of volatile metabolites produced by microorganisms. The usual metabolites such as methanol, ethanol, formic acid, 2-propanol (or acetone), 1-propanol, acetic acid, diacetyl, 1-butanol, propionic acid, acetoin, butyric acid, 2,3-butanediol and lactic acid were detected without any pretreatment. It was demonstrated that most strains of Bifidobacterium bifidum (Lactobacillus bifidus) produced both acetic acid and lactic acid which contrasts with results from Escherichia coli and other Lactobacilli.

Formation of transferable drug resistance factor by recombination between resistance determinants and transfer factors.

Abstract: Nontransferable drug resistance was acquired by conjugal transmissibility when mixed cultivation was applied to many isolates of the Enterobacteriaceae. The genetic element able to confer transmissibility on nontransferable drug resistance, was henceforth termed the transfer (T) factor. Genetic studies showed that there are three mechanisms involved in the acquisition of transferability of otherwise nontransferable drug resistance; (1) transfer of the drug resistance determinant on chromosome along with the transfer of host chromosome by T factor, (2) transfer of the nontransferable R factor by complementation with T factor, (3) formation of recombinant between the T factor and the drug resistance (r) determinant. The recombinant Tr factor was transferred as a single unit by the conjugal process, and was capable of conferring drug resistance. It was transduced jointly with bacteriophage P1 as a single unit in Escherichia coli.

Germination of B. anthracis spores in the peritoneal cavity of rats and establishment of anthrax.

Abstract: Most of spores of B. anthracis introduced into the peritoneal cavity of rats could germinate when 5 mg of L-alanine and 5 mg of adenosine were injected by the same route shortly before the spore injection. However the spores hardly germinated in untreated rats. To develop vegetative cells after spore germination, 1 ml of an aqueous solution containing 1% casamino acid and 1% of yeast extract was injected into the peritoneal cavity of rats before injection of 55×107 spores of B. anthracis. A few germinated spores and vegetative cells were seen in ascites, but their numbers were not enough to kill the rats. In order to produce a rapid germination and development to vegetative cells in a short time, 1 ml of solution containing 1% of casamino acid, 1% of yeast extract, 5 mg of L-alanine and 5 mg of adenosine was injected before intraperitoneal administration of spore suspension. Spore germination and vegetative growth were tremendous and all of rats died within 24 hours. From these results it was concluded that the natural resistance of the rat for B. anthracis is partly due to unfavorable internal conditions for spore germination and subsequent vegetative growth.

Integration of Chloramphenicol Resistance Gene of an R Factor on Escherichia coli Chromosome

Abstract: An unstable mutant R factor conferring only chloramphenicol (CM) resistance was obtained by spontaneous segregation. After storage in broth culture, a stable CM-resistant mutant was obtained and its CM-resistance could not be cured by treatment with acriflavine or transduced to a recombination-deficient strain of Escherichia coli K12. Recombinational analysis indicated that the cml gene governing CM resistance had been integrated into the E. coli chromosome and closely linked with met B locus. The cml gene was co-transduced with both met and arg markers by phage P1, and the linkage order was considered to be mtl-cml-met-arg-thi. When the strain carrying this chromosomal CM-resistance was infected with a transferable R (TC) factor capable of conferring tetracycline (TC) resistance, the CM-resistance became transferable by conjugation. This mechanism is considered to account for the formation of the recombinant R (TC.CM) factor.

In vivo Uncoating of Tobacco Mosaic Virus after Infection of Tobacco Leaves

Abstract: In vivo uncoating of tobacco mosaic virus (TMV) was studied. As Shaw had reported, initiation of uncoating reaction takes place very efficiently. Coat protein is removed from the virus as a peptide which is precipitable with trichloroacetic acid. Short rod particles with partly exposed RNA are thus formed. Further uncoating to coat protein-free TMV-RNA (28S) seems to take place with very low efficiency which is comparable to that of formation of local lesions on the inoculated leaf. From the data on the intracellular distribution of these products of uncoating reaction, mechanisms and significance of these reactions are discussed.

Experimental salmonellosis. Immunizing effect of live vaccine prepared from various mutants of Salmonella having different cell wall polysaccharides.

Abstract: Immunizing potencies of vaccines prepared from various strains of Salmonella were graded by comparing the mortality rate of immunized mice after challenge with highly virulent strains of either Salmonella enteritidis or S. typhimurium. The resistance against this challenge infection was shown to be conferred by joint immunization with a specific factor, which was represented by O specific lipopolysaccharide of smooth strains, and cross-protection factor, which was a major potent factor in live vaccine. The distribution of this cross-protection factor in rough mutants of S. typhimurium was found to be limited to strains which possessed a polysaccharide chain longer than that of glucose1-less mutant. The potency conferring cross-resistance was found to be maintained partly in formalin-killed cells and cell walls of the strains harboring cross-protection factor but not in lipopolysaccharide extracted from such strains.

Heat Resistance and α-Toxigenicity of Clostridium perfringens Strains in Normal Intestines of Japanese

Abstract: Heat-resistant strains of Clostridium perfringens were isolated from normal feces samples of Japanese people more frequently than from European people. However, the predominant number of the C. perfringens cells in the human intestines were sensitive to the heat at 100 C for 10 min. This proved to be true of the feces samples which were demonstrated to carry the organism resistant to 100 C for 60 min. Further studies indicated that the more the number of the organism in the intestines, the higher was the recovery ratio of the heat-resistant strains. Concomitant estimation for α-toxigenicity of those strains isolated from unheated feces samples revealed that the α-toxigenicity ranged mainly between 0.05 and 0.9 α-antitoxin equivalents.