Tadayo Hashimoto - Academia.edu (original) (raw)
Papers by Tadayo Hashimoto
Journal of Bacteriology, Mar 1, 1970
Some aspects of cell development and division of Bdellovibrio bacteriovorus strain UKi2 were exam... more Some aspects of cell development and division of Bdellovibrio bacteriovorus strain UKi2 were examined by use of electron microscopic techniques. Under saprophytic and parasitic conditions of growth, the comma-shaped cells enlarge, elongate, and form helical filaments. The mechanism of division appears to consist of an asymmetrical constriction of the filamentous cell by the cytoplasmic membrane, accompanied by a breakdown of the outer layers of the cell wall in the division region. During regeneration of the cell wall, the flagellum and flagellar sheath are formed. The development of the flagellum of the daughter cell is initiated prior to separation of the newly formed cells from the filament. Observations of B. bacteriovorus UKi2 grown under saprophytic and parasitic conditions indicate that development and ultrastructure are similar in both modes of growth. Cell development of obligately parasitic bdellovibrios has been observed by electron microscopy and other techniques (5, 8, 10-12, 14, 15). These observations indicate that the commashaped bdellovibrio within a bacterial host cell develops into a coiled or spiral-shaped cell. The bdellovibrio spiral then divides by a constrictive process into a number of progeny cells (5, 8, 12). A facultatively parasitic Bdellovibrio bacteriovorus (strain UKi2), i.e., a bdellovibrio which can grow endoparasitically in a bacterial host or saprophytically in a bacterial-free medium, was isolated and characterized in our laboratory (3). Cell elongation, cell division, flagellar development, and fine structural changes, all of which are difficult to follow in obligately parasitic bdellovibrios because of the confining host bacteria, were observed in host-free environments and were related to parasitic development. MATERIALS AND METHODS Organisms. The isolation and characterization of B. bacteriovorus strain UKi2 has been described (3). The host bacterium employed was Escherichia coli B/r. Cultural conditions. All cultures were grown in 100
Infection and Immunity, 1991
Activated peritoneal macrophages obtained from Listeria-immune mice were demonstrated to kill non... more Activated peritoneal macrophages obtained from Listeria-immune mice were demonstrated to kill nonphagocytosable Candida albicans hyphae by contact-mediated mechanisms in a serum-free synthetic medium. The actual killing of hyphae was confirmed by a microculture technique utilizing the dimorphic nature of the fungus. The most efficient candidacidal activity was demonstrated by the macrophages obtained from mice first immunized with live Listeria monocytogenes and then elicited with heat-killed L. monocytogenes cells. Resident macrophages from control mice showed only low candidacidal activity against C. albicans hyphae and yeast cells. Direct physical contact appeared to be required for macrophages to efficiently kill oversized C. albicans hyphae. Efficient in vitro killing of hyphae also required relatively high effector/target cell ratios (50 or higher). The contact-mediated candidacidal activity of activated macrophages was not significantly abrogated by oxygen-radical scavengers,...
Changes in refractility and optical density occurring in individual spores of Bacillus cereus T a... more Changes in refractility and optical density occurring in individual spores of Bacillus cereus T and B. megaterium QM B1551 during germination were investigated by use of a Zeiss microscope photometer. The curves revealed that the germination process in single spores had two distinct phases; an initial rapid phase was followed by a second slower phase. Under the experimental condition employed, the first phase of germination of B. cereus spores lasted for approximately 75 i 15 sec, whereas the second phase lasted for 3 to 4.5 min. In B. megaterium spores, the first phase was observed to last for approximately 2 min and the second phase for more than 7 min. The duration of the second phase was dependent on conditions employed for germination. The kinetics of the first phase were strikingly similar under all conditions of physiological germination. Time-lapse phase-contrast microscopy of germinating spores also revealed the biphasic nature of germination. It was postulated that the fir...
Infection and Immunity, 1977
Nutritional and environmental factors affecting germination of Trichophyton mentagrophytes arthro... more Nutritional and environmental factors affecting germination of Trichophyton mentagrophytes arthrospores were investigated. Germination of dormant arthrospores occurred only in rich complex media such as Sabouraud dextrose broth or vitamin-free Casamino Acids. However, once activated, arthrospores were able to germinate under wide ranges of pH (5.5 to 8.0, optimal 6.5) and temperature (20 to 39 degrees C, optimal 37 degrees C) in the presence of certain single amino acids or oligopeptides known to be present in the human cutaneous tissues. Dormant arthrospores could be activated by incubation in distilled water at 25 degrees C for 24 h or by brief exposure to sublethal doses of heat (45 degrees C for 10 to 20 min). Approximately 20% of activated arthrospores underwent spontaneous germination at 37 degrees C during an additional 18 h of incubation in distilled water. All monosaccharides, purines, pyrimidines, and nucleosides tested failed to induce germination of T. mentagrophytes art...
Journal of Bacteriology, 1970
The sequence of events occurring during the germination and outgrowth of appendage-bearing spores... more The sequence of events occurring during the germination and outgrowth of appendage-bearing spores of Clostridium bifermentans was studied by phase-contrast and electron microscopy. The mature spore was characterized ultrastructurally as having the normal spore components as well as long tubular appendages which orginated from the surface of the spore coat. Spores were incompletely enclosed by a distinctly laminated exosporium which possessed hairlike projections on its outermost layer. During germination, structural changes were observed in the core, core wall, cortex, and spore coat layers. Cortical material was extruded from the spore during outgrowth, which usually occurred from the pole opposite the appendages. The subunits comprising the structure of the appendages and the morphology of the mature appendages were observed. No discernible changes could be observed in the spore appendages during germination and outgrowth.
Journal of Bacteriology, 1969
The biphasic nature of germination curves of individual Bacillus cereus T spores was further char... more The biphasic nature of germination curves of individual Bacillus cereus T spores was further characterized by assessing the effects of temperature, concentration of germinants, and some inorganic cations on microgermination. Temperature was shown to affect both phases of microgermination as well as the microlag period, whereas the concentration of l -alanine and supplementation with adenosine exerted a significant effect only on the microlag period. The germination curves of individual spores induced by inosine were also biphasic and resembled those of spores induced by l -alanine. High concentrations (0.1 m or higher) of calcium and other inorganic cations prolonged both phases of microgermination, particularly the second phase, and had a less pronounced effect on the microlag period. The second phase of microgermination was completely inhibited when spores were germinated either in the presence of 0.3 m CaCl 2 or at a temperature of 43 C; this inhibition was reversible. Observatio...
Journal of Bacteriology, 1970
A strain of Bdellovibrio bacteriovorus (designated strain UKi2) was isolated which was capable of... more A strain of Bdellovibrio bacteriovorus (designated strain UKi2) was isolated which was capable of growing either saprophytically in host-free medium or endoparasitically in Escherichia coli B/r. It was quantitatively determined that each bdellovibrio could develop in solid medium to produce a colony, and 65% of the cells in a late exponential-phase culture were capable of inducing E. coli B/r spheroplasts. A photomicrographic sequence of single E. coli spheroplasts containing bdellovibrios demonstrated that parasitically derived B. bacteriovorus UKi2 could develop saprophytically after release from the host cells. Strain UKi2 appears to be morphologically quite similar to previously described obligately parasitic bdellovibrios; biochemical data on this strain suggests its close relationship to some of the previously described host-independent strains of Bdellovibrio .
Applied and Environmental Microbiology, 1984
Evidence is presented for the presence of trace amounts of ethanol in certain commercial buffers.... more Evidence is presented for the presence of trace amounts of ethanol in certain commercial buffers. It was shown that germ tube formation occurring in Candida albicans suspended in the buffers was due to the contaminating ethanol.
Journal of Bacteriology, 1976
The rodlet layer of the microconidial wall of Trichophyton mentagrophytes was isolated and partia... more The rodlet layer of the microconidial wall of Trichophyton mentagrophytes was isolated and partially characterized. The purified microconidial walls were first extracted with urea (8M), mercaptoethanol (1%), and sodium dodecyl sulfate (1%) followed by enzymatic digestion with glusulase (snail intestinal enzymes) and purified (1 leads to 3)-beta-D-glucanase and chitinase. The purified rodlet layer was 15 to 30 nm thick and accounted for approximately 10% of the original wall weight. The pattern of rodlet patches, as revealed by electron microscopy of freeze-etched preparations of the isolated layer, was essentially the same as that observed on the intact microconidial wall. The rodlet layer was found to be resistant to most of the common organic solvents, cell wall lytic enzymes, mild acid treatments, and surface-active agents, but was solubilized in boiling 1 N NaOH with concomitant disorientation of the rodlet patterns. A melanin or melanin-like pigment appeared to be intimately as...
Journal of Bacteriology, 1969
Electron microscopy of serial sections of Escherichia coli K-12 (P678-54) revealed that some “min... more Electron microscopy of serial sections of Escherichia coli K-12 (P678-54) revealed that some “minicells” contain nuclear bodies.
Tokushima Journal of Experimental Medicine, 1966
Microbiology and Immunology, 1993
Biphasic germination induced by inosine in the presence of Ca2+ was examined using Bacillus cereu... more Biphasic germination induced by inosine in the presence of Ca2+ was examined using Bacillus cereus T spores treated with sodium dodecyl sulfate (SDS) and dithiothreitol (DTT) at pH 10. The first phase of the germination was stimulated by Ca2+ in the concentration‐dependent manner, showing the optimal concentration at 0.5‐1.0 mM. The second phase appeared to be insensitive to the cation. The optimal temperatures for the first and the second phase were 25 C and 40 C, respectively; the optimal pHs for the two phases were 7‐9 and around 7.5, respectively. Heat resistance and dipicolinic acid of the SDS‐DTT‐treated spores were lost mostly during the first phase. A Ca2+‐specific chelator, glycoletherdiamine‐N,N,N',N'‐tetraacetic acid (GEDTA), inhibited the first phase evoked by Ca2+, while it had no inhibitory effect on the second phase. In contrast, the divalent cations examined, except Mg2+ and Sr2+, affected not only the first phase but also the second phase. The order of inhib...
Canadian Journal of Microbiology, 1960
A correlative study was made of some structural and functional features of a reasonably synchroni... more A correlative study was made of some structural and functional features of a reasonably synchronized culture of Bacillus cereus strain terminalis during spore formation and maturation. The successive stages of development could be recognized by phase contrast microscopy and in electron micrographs of ultra-thin-sectioned cells. Attempts were made to correlate these changes with the acquisition of heat resistance and the synthesis of dipicolinic acid. The outer coat of the spores was observed to be formed first around the forespore; the exosporium, cortex, and inner coat then appeared sequentially and independently of existing sporangial membranes. Dipicolinic acid synthesis began in the early transitional stage, just after forespore formation, and reached one third of the maximum level before an increase of heat resistance in the population was detectable, indicating the possibility of a correlation only above a threshold level of the compound.
Canadian Journal of Microbiology, 1986
Purine riboside and some of its analogs were tested for their ability to induce germination of Ba... more Purine riboside and some of its analogs were tested for their ability to induce germination of Bacillus cereus T spores. Hypoxanthine and adenine showed no germination-inducing activity either in the present or absence of D-ribose or its phosphorylated derivatives. Purine riboside and 18 analogs with modified purine base were all able to induce germination of the spores to various extents. In contrast to this, the requirement for the sugar moiety in the purine riboside appeared to be more stringent. Only those nucleosides that contained either D-ribose or deoxy-D-ribose, and certain species of azole derivatives such as 5-aminoimidazole-4-carboxamide covalently linked to the C(1′) of the sugar actively induced germination.
Tuberculosis is the most prevalent infectious disease in the world. It occurs globally but predom... more Tuberculosis is the most prevalent infectious disease in the world. It occurs globally but predominantly in developing countries where the standard of living is lagging behind the industrialized nations. In Japan, tuberculosis was once the leading cause of death. With the advent of medical sciences and the improved economic condition, the incidence of tuberculosis in Japan started to decline after the World War II continuing until early 1970 s. It was estimated that tuberculosis would become a disease of the past not in the far distant future. However, this optimistic prediction was proved to be wrong. The continued decline of tuberculosis cases in Japan was eventually replaced by increase in 1997. The subsequent yearly increase of the disease prompted the government to declare the state of emergency in the epidemic of tuberculosis. Clearly, the past policies and efforts to eliminate tuberculosis have not been successful leaving tuberculosis largely uncontrolled in Japan. It is hard...
Journal of Bacteriology, Dec 1, 1978
Carotenoid pigments were demonstrated in arthrospores of the dermatophyte Trichophyton mentagroph... more Carotenoid pigments were demonstrated in arthrospores of the dermatophyte Trichophyton mentagrophytes but were absent from hyphae and microconidia of this fungus. Incubation at higher temperatures (39°C) allowed arthrosporulation to occur, but essentially no carotenoid was detected in such arthrospores. The carotenoid formation in arthrosporulating T. mentagrophytes did not appear to be either induced or stimulated by light illumination. Mature arthrospores contained the carotenoids phytoene, phytofluene, D-carotene, neurosporene, lycopene, and y-carotene and a few minor unidentified carotenoids. These carotenoids were localized within intracellular granules consisting of osmiophilic matrices and complex membranous elements. This is the first demonstration of carotenoid pigments in dermatophytic fungi. Dermatophytes are a group of fungi responsible for ringworm infections in humans and animals. Many strains of dermatophytes produce
Journal of Bacteriology, 1958
Development of the ultrathin sectioning technique for electron microscopy has proved to be an inv... more Development of the ultrathin sectioning technique for electron microscopy has proved to be an invaluable aid in the exploration and elucidation of the fine structural components of various biological systems. The introduction of this technique to bacterial cytology has served to clarify or solve some of the long-standing disputes regarding the structure of bacteria (Chap
Journal of Bacteriology, Mar 1, 1970
Some aspects of cell development and division of Bdellovibrio bacteriovorus strain UKi2 were exam... more Some aspects of cell development and division of Bdellovibrio bacteriovorus strain UKi2 were examined by use of electron microscopic techniques. Under saprophytic and parasitic conditions of growth, the comma-shaped cells enlarge, elongate, and form helical filaments. The mechanism of division appears to consist of an asymmetrical constriction of the filamentous cell by the cytoplasmic membrane, accompanied by a breakdown of the outer layers of the cell wall in the division region. During regeneration of the cell wall, the flagellum and flagellar sheath are formed. The development of the flagellum of the daughter cell is initiated prior to separation of the newly formed cells from the filament. Observations of B. bacteriovorus UKi2 grown under saprophytic and parasitic conditions indicate that development and ultrastructure are similar in both modes of growth. Cell development of obligately parasitic bdellovibrios has been observed by electron microscopy and other techniques (5, 8, 10-12, 14, 15). These observations indicate that the commashaped bdellovibrio within a bacterial host cell develops into a coiled or spiral-shaped cell. The bdellovibrio spiral then divides by a constrictive process into a number of progeny cells (5, 8, 12). A facultatively parasitic Bdellovibrio bacteriovorus (strain UKi2), i.e., a bdellovibrio which can grow endoparasitically in a bacterial host or saprophytically in a bacterial-free medium, was isolated and characterized in our laboratory (3). Cell elongation, cell division, flagellar development, and fine structural changes, all of which are difficult to follow in obligately parasitic bdellovibrios because of the confining host bacteria, were observed in host-free environments and were related to parasitic development. MATERIALS AND METHODS Organisms. The isolation and characterization of B. bacteriovorus strain UKi2 has been described (3). The host bacterium employed was Escherichia coli B/r. Cultural conditions. All cultures were grown in 100
Infection and Immunity, 1991
Activated peritoneal macrophages obtained from Listeria-immune mice were demonstrated to kill non... more Activated peritoneal macrophages obtained from Listeria-immune mice were demonstrated to kill nonphagocytosable Candida albicans hyphae by contact-mediated mechanisms in a serum-free synthetic medium. The actual killing of hyphae was confirmed by a microculture technique utilizing the dimorphic nature of the fungus. The most efficient candidacidal activity was demonstrated by the macrophages obtained from mice first immunized with live Listeria monocytogenes and then elicited with heat-killed L. monocytogenes cells. Resident macrophages from control mice showed only low candidacidal activity against C. albicans hyphae and yeast cells. Direct physical contact appeared to be required for macrophages to efficiently kill oversized C. albicans hyphae. Efficient in vitro killing of hyphae also required relatively high effector/target cell ratios (50 or higher). The contact-mediated candidacidal activity of activated macrophages was not significantly abrogated by oxygen-radical scavengers,...
Changes in refractility and optical density occurring in individual spores of Bacillus cereus T a... more Changes in refractility and optical density occurring in individual spores of Bacillus cereus T and B. megaterium QM B1551 during germination were investigated by use of a Zeiss microscope photometer. The curves revealed that the germination process in single spores had two distinct phases; an initial rapid phase was followed by a second slower phase. Under the experimental condition employed, the first phase of germination of B. cereus spores lasted for approximately 75 i 15 sec, whereas the second phase lasted for 3 to 4.5 min. In B. megaterium spores, the first phase was observed to last for approximately 2 min and the second phase for more than 7 min. The duration of the second phase was dependent on conditions employed for germination. The kinetics of the first phase were strikingly similar under all conditions of physiological germination. Time-lapse phase-contrast microscopy of germinating spores also revealed the biphasic nature of germination. It was postulated that the fir...
Infection and Immunity, 1977
Nutritional and environmental factors affecting germination of Trichophyton mentagrophytes arthro... more Nutritional and environmental factors affecting germination of Trichophyton mentagrophytes arthrospores were investigated. Germination of dormant arthrospores occurred only in rich complex media such as Sabouraud dextrose broth or vitamin-free Casamino Acids. However, once activated, arthrospores were able to germinate under wide ranges of pH (5.5 to 8.0, optimal 6.5) and temperature (20 to 39 degrees C, optimal 37 degrees C) in the presence of certain single amino acids or oligopeptides known to be present in the human cutaneous tissues. Dormant arthrospores could be activated by incubation in distilled water at 25 degrees C for 24 h or by brief exposure to sublethal doses of heat (45 degrees C for 10 to 20 min). Approximately 20% of activated arthrospores underwent spontaneous germination at 37 degrees C during an additional 18 h of incubation in distilled water. All monosaccharides, purines, pyrimidines, and nucleosides tested failed to induce germination of T. mentagrophytes art...
Journal of Bacteriology, 1970
The sequence of events occurring during the germination and outgrowth of appendage-bearing spores... more The sequence of events occurring during the germination and outgrowth of appendage-bearing spores of Clostridium bifermentans was studied by phase-contrast and electron microscopy. The mature spore was characterized ultrastructurally as having the normal spore components as well as long tubular appendages which orginated from the surface of the spore coat. Spores were incompletely enclosed by a distinctly laminated exosporium which possessed hairlike projections on its outermost layer. During germination, structural changes were observed in the core, core wall, cortex, and spore coat layers. Cortical material was extruded from the spore during outgrowth, which usually occurred from the pole opposite the appendages. The subunits comprising the structure of the appendages and the morphology of the mature appendages were observed. No discernible changes could be observed in the spore appendages during germination and outgrowth.
Journal of Bacteriology, 1969
The biphasic nature of germination curves of individual Bacillus cereus T spores was further char... more The biphasic nature of germination curves of individual Bacillus cereus T spores was further characterized by assessing the effects of temperature, concentration of germinants, and some inorganic cations on microgermination. Temperature was shown to affect both phases of microgermination as well as the microlag period, whereas the concentration of l -alanine and supplementation with adenosine exerted a significant effect only on the microlag period. The germination curves of individual spores induced by inosine were also biphasic and resembled those of spores induced by l -alanine. High concentrations (0.1 m or higher) of calcium and other inorganic cations prolonged both phases of microgermination, particularly the second phase, and had a less pronounced effect on the microlag period. The second phase of microgermination was completely inhibited when spores were germinated either in the presence of 0.3 m CaCl 2 or at a temperature of 43 C; this inhibition was reversible. Observatio...
Journal of Bacteriology, 1970
A strain of Bdellovibrio bacteriovorus (designated strain UKi2) was isolated which was capable of... more A strain of Bdellovibrio bacteriovorus (designated strain UKi2) was isolated which was capable of growing either saprophytically in host-free medium or endoparasitically in Escherichia coli B/r. It was quantitatively determined that each bdellovibrio could develop in solid medium to produce a colony, and 65% of the cells in a late exponential-phase culture were capable of inducing E. coli B/r spheroplasts. A photomicrographic sequence of single E. coli spheroplasts containing bdellovibrios demonstrated that parasitically derived B. bacteriovorus UKi2 could develop saprophytically after release from the host cells. Strain UKi2 appears to be morphologically quite similar to previously described obligately parasitic bdellovibrios; biochemical data on this strain suggests its close relationship to some of the previously described host-independent strains of Bdellovibrio .
Applied and Environmental Microbiology, 1984
Evidence is presented for the presence of trace amounts of ethanol in certain commercial buffers.... more Evidence is presented for the presence of trace amounts of ethanol in certain commercial buffers. It was shown that germ tube formation occurring in Candida albicans suspended in the buffers was due to the contaminating ethanol.
Journal of Bacteriology, 1976
The rodlet layer of the microconidial wall of Trichophyton mentagrophytes was isolated and partia... more The rodlet layer of the microconidial wall of Trichophyton mentagrophytes was isolated and partially characterized. The purified microconidial walls were first extracted with urea (8M), mercaptoethanol (1%), and sodium dodecyl sulfate (1%) followed by enzymatic digestion with glusulase (snail intestinal enzymes) and purified (1 leads to 3)-beta-D-glucanase and chitinase. The purified rodlet layer was 15 to 30 nm thick and accounted for approximately 10% of the original wall weight. The pattern of rodlet patches, as revealed by electron microscopy of freeze-etched preparations of the isolated layer, was essentially the same as that observed on the intact microconidial wall. The rodlet layer was found to be resistant to most of the common organic solvents, cell wall lytic enzymes, mild acid treatments, and surface-active agents, but was solubilized in boiling 1 N NaOH with concomitant disorientation of the rodlet patterns. A melanin or melanin-like pigment appeared to be intimately as...
Journal of Bacteriology, 1969
Electron microscopy of serial sections of Escherichia coli K-12 (P678-54) revealed that some “min... more Electron microscopy of serial sections of Escherichia coli K-12 (P678-54) revealed that some “minicells” contain nuclear bodies.
Tokushima Journal of Experimental Medicine, 1966
Microbiology and Immunology, 1993
Biphasic germination induced by inosine in the presence of Ca2+ was examined using Bacillus cereu... more Biphasic germination induced by inosine in the presence of Ca2+ was examined using Bacillus cereus T spores treated with sodium dodecyl sulfate (SDS) and dithiothreitol (DTT) at pH 10. The first phase of the germination was stimulated by Ca2+ in the concentration‐dependent manner, showing the optimal concentration at 0.5‐1.0 mM. The second phase appeared to be insensitive to the cation. The optimal temperatures for the first and the second phase were 25 C and 40 C, respectively; the optimal pHs for the two phases were 7‐9 and around 7.5, respectively. Heat resistance and dipicolinic acid of the SDS‐DTT‐treated spores were lost mostly during the first phase. A Ca2+‐specific chelator, glycoletherdiamine‐N,N,N',N'‐tetraacetic acid (GEDTA), inhibited the first phase evoked by Ca2+, while it had no inhibitory effect on the second phase. In contrast, the divalent cations examined, except Mg2+ and Sr2+, affected not only the first phase but also the second phase. The order of inhib...
Canadian Journal of Microbiology, 1960
A correlative study was made of some structural and functional features of a reasonably synchroni... more A correlative study was made of some structural and functional features of a reasonably synchronized culture of Bacillus cereus strain terminalis during spore formation and maturation. The successive stages of development could be recognized by phase contrast microscopy and in electron micrographs of ultra-thin-sectioned cells. Attempts were made to correlate these changes with the acquisition of heat resistance and the synthesis of dipicolinic acid. The outer coat of the spores was observed to be formed first around the forespore; the exosporium, cortex, and inner coat then appeared sequentially and independently of existing sporangial membranes. Dipicolinic acid synthesis began in the early transitional stage, just after forespore formation, and reached one third of the maximum level before an increase of heat resistance in the population was detectable, indicating the possibility of a correlation only above a threshold level of the compound.
Canadian Journal of Microbiology, 1986
Purine riboside and some of its analogs were tested for their ability to induce germination of Ba... more Purine riboside and some of its analogs were tested for their ability to induce germination of Bacillus cereus T spores. Hypoxanthine and adenine showed no germination-inducing activity either in the present or absence of D-ribose or its phosphorylated derivatives. Purine riboside and 18 analogs with modified purine base were all able to induce germination of the spores to various extents. In contrast to this, the requirement for the sugar moiety in the purine riboside appeared to be more stringent. Only those nucleosides that contained either D-ribose or deoxy-D-ribose, and certain species of azole derivatives such as 5-aminoimidazole-4-carboxamide covalently linked to the C(1′) of the sugar actively induced germination.
Tuberculosis is the most prevalent infectious disease in the world. It occurs globally but predom... more Tuberculosis is the most prevalent infectious disease in the world. It occurs globally but predominantly in developing countries where the standard of living is lagging behind the industrialized nations. In Japan, tuberculosis was once the leading cause of death. With the advent of medical sciences and the improved economic condition, the incidence of tuberculosis in Japan started to decline after the World War II continuing until early 1970 s. It was estimated that tuberculosis would become a disease of the past not in the far distant future. However, this optimistic prediction was proved to be wrong. The continued decline of tuberculosis cases in Japan was eventually replaced by increase in 1997. The subsequent yearly increase of the disease prompted the government to declare the state of emergency in the epidemic of tuberculosis. Clearly, the past policies and efforts to eliminate tuberculosis have not been successful leaving tuberculosis largely uncontrolled in Japan. It is hard...
Journal of Bacteriology, Dec 1, 1978
Carotenoid pigments were demonstrated in arthrospores of the dermatophyte Trichophyton mentagroph... more Carotenoid pigments were demonstrated in arthrospores of the dermatophyte Trichophyton mentagrophytes but were absent from hyphae and microconidia of this fungus. Incubation at higher temperatures (39°C) allowed arthrosporulation to occur, but essentially no carotenoid was detected in such arthrospores. The carotenoid formation in arthrosporulating T. mentagrophytes did not appear to be either induced or stimulated by light illumination. Mature arthrospores contained the carotenoids phytoene, phytofluene, D-carotene, neurosporene, lycopene, and y-carotene and a few minor unidentified carotenoids. These carotenoids were localized within intracellular granules consisting of osmiophilic matrices and complex membranous elements. This is the first demonstration of carotenoid pigments in dermatophytic fungi. Dermatophytes are a group of fungi responsible for ringworm infections in humans and animals. Many strains of dermatophytes produce
Journal of Bacteriology, 1958
Development of the ultrathin sectioning technique for electron microscopy has proved to be an inv... more Development of the ultrathin sectioning technique for electron microscopy has proved to be an invaluable aid in the exploration and elucidation of the fine structural components of various biological systems. The introduction of this technique to bacterial cytology has served to clarify or solve some of the long-standing disputes regarding the structure of bacteria (Chap