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1.
Kuniyoshi Masuda Tomio Kawata Kenji Takumi Takemi Kinouchi 《Microbiology and immunology》1980,24(6):507-513
The ultrastructure of a hexagonal array in the exosporium from spores of a highly sporogenic mutant of Clostridium botulinum type A strain 190L was studied by electron microscopy of negatively stained exosporium fragments using optical diffraction and filtration. The exosporium was composed of three or more lamellae showing an equilateral, hexagonal periodicity. Images of the single exosporium layer from which the noise had been filtered optically revealed that the hexagonally arranged, morphological unit of the exosporium was composed of three globular subunits about 2.1 nm in diameter which were arranged at the vertices of an equilateral triangle with sides of about 2.4 nm. The morphological units were arranged with a spacing of about 4.5 nm. The adjacent globular subunits appeared to be interconnected by delicate linkers. 相似文献
2.
Kenji Tsuji Shinji KitamuraHirofumi Makino 《Biochemical and biophysical research communications》2014
The kidneys are exposed to hypoxic conditions during development. Hypoxia-inducible factor (HIF), an important mediator of the response to hypoxia, is believed to have an important role in development. However, the relationship between HIF and branching morphogenesis has not been elucidated clearly. 相似文献
3.
Y Ishikawa K Kobayashi K Seki H Mizutani Y Kawasaki J Koike K Ijiri M Yamashita K Sugiura J Poynter T MacCallum G Anderson 《Biological Sciences in Space》1998,12(4):366-372
Several soluble components, peptidase and amino acids, and carbon isotopic ratio in the water retrieved from flight experiments of Autonomous Biological Systems (ABS) as well as ground control samples are analyzed to interpret the condition, dynamics, material balance of the ABS ecosystems. Organic carbons in flight samples were found to be more abundant compared with the control ones, which suggested the uniform ecosystems in low gravity might easily dissolve more soluble components. The Mir-1997 flight sample showed higher C/N ratio probably because of the dissolution of carbon-rich plant materials. 相似文献
4.
Nontoxigenic variants were isolated from Clostridium botulinum type A strain 190L after treatment with detergents such as deoxycholate, sodium dodecyl sulfate, Tween 80 and Brij-58. Deoxycholate was most effective for obtaining the variants. The variants exhibited a markedly increased frequency of sporulation compared with the oligosporogenic parent strain. The cell wall of the parent strain was composed of an outer layer and an inner layer, whereas that of the variants lost the outer layer. After treatment with mitomycin C the parent strain was subjected to lysis and produced bacteriophages with a hexagonal head and a contractible tail, while the nontoxigenic variants did not yield bacteriophages or phage-like structures. There appears to be a close relationship among the toxigenic and sporogenic properties, formation of the outer cell wall layer and lysogeny. 相似文献
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7.
Kenji Mori 《Bioscience, biotechnology, and biochemistry》2013,77(13):2563-2567
Methyl dl-12-homo-10-trans-juvenate (III) was synthesized from farnesol (IV) in eight steps involving stereoselective conversion of the trans-terminal methyl group to an ethyl group. The product (III) was less active than dl-C17-Cecropia juvenile hormone on both Tenebrio molitor and Galleria mellonella. 相似文献
8.
Yuichi Esaki Kenji Obayashi Keigo Saeki Kiyoshi Fujita Nakao Iwata Tsuyoshi Kitajima 《Chronobiology international》2020,37(6):887-896
ABSTRACT Previous studies have found that keeping the room dark at night was associated with a decrease in manic symptoms for patients with bipolar disorder (BD). However, the association between light at night of real-life conditions and manic symptoms is unclear. We investigated the association between bedroom light exposure at night and manic symptoms in BD patients. One-hundred and eighty-four outpatients with BD participated in this cross-sectional study. The average light intensity at night during sleep was evaluated using a portable photometer for seven consecutive nights. Manic symptoms were assessed using the Young Mania Rating Scale (YMRS), and scores ≥5 were treated as a “hypomanic state.” The median (interquartile range) YMRS score was 2.0 (0–5.0), and 52 (28.2%) participants were in a hypomanic state. The prevalence of a hypomanic state was significantly higher in the participants with an average light intensity at night exposure of ≥3 lux than in those with <3 lux (36.7% versus 21.9%; P = .02). In multivariable logistic regression analysis adjusted for BD type, depressive symptoms, sleep duration, and daytime physical activity, the odds ratio (OR) for a hypomanic state was significantly higher for the participants with an average light intensity at night exposure of ≥3 lux than for those with <3 lux (OR: 2.15, 95% confidence interval: 1.09–4.22, P = .02). This association remained significant at the cutoff value of YMRS score ≥6 (OR: 2.51, 95% confidence interval: 1.15–5.46; P = .02). The findings of this study indicate bedroom light exposure at night is significantly associated with manic symptoms in BD patients. Although the results of this cross-sectional investigation do not necessarily imply causality, they may serve to inform beneficial nonpharmacological intervention and personalized treatment of BD patients. 相似文献
9.
M Yamashita S Konagaya 《Comparative biochemistry and physiology. B, Comparative biochemistry》1990,96(2):247-252
1. Cathepsin L of the white muscle of chum salmon (Oncorhynchus keta) in spawning migration was purified to homogeneity by a series of chromatography on DEAE-Sephadex (1st), SP-Sephadex, CM-Sephadex, DEAE-Sephadex (2nd) and Sephadex G-100. 2. The molecular weight of salmon muscle cathepsin L was estimated to be 30,000 and its isoelectric point was 5.2. 3. Cathepsin L had a pH optimum of 5.6, required a thiol-reducing reagent for activation, and was inhibited by cysteine protease inhibitors. 4. The Km and kcat values for Z-Phe-Arg-MCA were determined to be 1.68 microM and 15.8 s-1, respectively. This enzyme hydrolyzed proteins such as insulin B chain, hemoglobin, serum albumin and azocasein easily. 5. The bond specificity to oxidized insulin B chain inferred that the enzyme had a preference for hydrophobic amino acid in P2 and P3 residues. 相似文献
10.
Tomonori Murakami Kenji Hiraoka Takeshi Mikami Tatsuji Matsumoto Susumu Katagiri Kunihiro Shinagawa Masuko Suzuki 《FEMS microbiology letters》1993,107(2-3):179-183
Abstract Flagellar antigen of Bacillus cereus H.1 was purified and tested for serodiagnostic antigen by ELISA. The antibody against the flagellar antigen of B. cereus H.1 reacted not only with the homologous specific antigen but also reacted with the flagellar antigens of 23 strains of B. cereus . This common flagellar antigen of B. cereus was found to be due to 61-kDa protein by SDS-PAGE and immunoblot assay. Monoclonal antibody H15A5 against common antigenic epitope of B. cereus also reacted with flagellar antigens of 21 strains of Bacillus thuringiensis by ELISA. This monoclonal antibody reacted with the 61-kDa protein of the flagella of B. cereus H.1 and H.2 and B. thuringiensis Kurstaki HD1, Alesti and Aizawai juroi by immunoblot analysis. These results indicated that the common antigenic epitope of the 61-kDa protein existed in the flagella both of B. cereus and B. thuringiensis . 相似文献