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41.
Masahiko Sakaguchi Kazumitsu Hanai Kunimasa Ohta Masaaki Kitajima Sachiko Matsuhashi Katsuji Hori Hiromichi Morita 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1991,168(4):409-416
Summary Reduced glutathione evokes a feeding response, the tentacle-ball formation inHydra japonica. This response consists of at least 5 components (R1–R5). We raised 6 monoclonal antibodies (mAbs), each of which depressed a specific subset of these components, and we also examined the immunocytochemical localization of antigens with these mAbs at light microscopic level. The 2 mAbs that depressed R2 and R4 bound to the cnidocils of the desmoneme and the stenotele nematocytes; the 3 mAbs that depressed R5 bound to the apical surface adjacent to the cnidocils of the nematocytes; and the 2 mAbs that depressed R1 and R3 bound to the apical spot structures of unidentified cells in the ectoderm.Together with the specificity of the action of the mAbs on the behavioral response, the correspondence between the effects on the response and the structures visualized with these mAbs suggests that these structures include components of the receptor-effector system relevant to chemoreception. 相似文献
42.
43.
T Masaki H Umehashi H Miyazaki M Takano K Yamakawa S Nakamura 《Japanese journal of medical science & biology》1988,41(1):27-30
A Clostridium perfringens-like strain was isolated from a case of gas gangrene. The morphological properties and the lecithinase reaction of the isolate were very similar to those of C. perfringens; however, the lecithinase reaction was only slightly suppressed by C. perfringens alpha-antitoxin serum and the organism was identified as Clostridium absonum from its biochemical properties. 相似文献
44.
Electron paramagnetic resonance (EPR) spectra of ferrous-nitric oxide (14NO and 15NO) cytochrome P-450scc complexed with 20(R),22(R)-dihydroxycholesterol were measured at 77 K with X-band (9.35 GHz) microwave frequency. The EPR spectra clearly showed the spin system to have rhombic symmetry (gx = 2.068, gz = 2.001, gy = 1.961, and Az = 1.89 mT for 14NO) and were distinct from those of 20(S)-hydroxycholesterol complexes. The unique nature of the 20(S)-hydroxycholesterol complexes indicates that 20(S)-hydroxycholesterol is not a proper intermediate in the cholesterol side-chain cleavage reaction. In addition, among various steroid complexes of ferrous-NO species having rhombic symmetry, the EPR spectra of 20(R),22(R)-dihydroxycholesterol complexes were significantly different from those of 22(R)-hydroxycholesterol complexes, suggesting that upon 20S-hydroxylation of 22(R)-hydroxycholesterol the conformation of the active site changes so as to facilitate subsequent cleavage of the C20-C22 bond of the cholesterol side chain. Addition of reduced adrenodoxin to the ferrous-NO cytochrome P-450scc complex in the presence of cholesterol caused a complete shift of the gx = 2.070 signal to gx = 2.075, indicating a reorientation of cholesterol in the substrate-binding site of the enzyme upon adrenodoxin binding. Without reduced adrenodoxin, the process of reorientation of cholesterol in the substrate-binding site was very slow, requiring more than 50 h of incubation at 0 degrees C. The present observations suggest that adrenodoxin may have another positive role in the cholesterol side-chain cleavage reaction, in addition to transferring an electron to the heme of cytochrome P-450scc. 相似文献
45.
W Huang T Kimura K Mashima K Miyazaki H Masaki J Yamashita T Horio 《Journal of biochemistry》1986,100(3):687-696
We previously reported that sera from various kinds of animals contain a protein(s) capable of inhibiting the growth of the non-malignant epithelial cell line derived from Buffalo rat liver (BRL). In the present study, a similar epithelial cell-specific growth inhibitor (EGI) was purified to homogeneity from an acid-ethanol extract of human platelets. During purification, EGI was separated from the major component of type beta transforming growth factor (TGF-beta), which can stimulate the colony formation of the non-malignant fibroblastic cell line derived from rat kidney (NRK) in soft agar in the presence of epidermal growth factor (EGF). The purified EGI had an Mr of 27,000, and was composed of two subunits identical in Mr. It significantly inhibited the growth in monolayer cultures of three non-malignant epithelial cell lines, BRL, MDCK (from Madin-Darby canine kidney) and BSC-1 (from African green monkey kidney), at doses lower than 40 pg/ml in medium containing 10% fetal calf serum. Its inhibitory activity was stable against heating at 90 degrees C for 3 min, but not against treatment with 50 mM dithiothreitol. In addition, TGF-beta was also partially purified from the same extract. The purified TGF-beta did not show any inhibitory activity toward the growth of BRL, MDCK, BSC-1, or NRK. 相似文献
46.
T Masaki H Takano-Ohmuro H Iizuka J Okamoto T Obinata 《Journal of biochemistry》1986,100(4):1091-1094
A distinct difference in the 3-methylhistidine (3-MeHis) content and the pH-dependency curve for calcium-activated adenosine triphosphatase (Ca-ATPase) activity was observed between chicken and mammalian cardiac ventricular myosins. The 3-MeHis content and pH dependency of the Ca-ATPase activity of myosins from adult and embryonic chicken cardiac ventricular muscles and chicken fast white and slow red muscles were almost the same. 相似文献
47.
M Kasahara K Inui M Takano R Hori 《Biochemical and biophysical research communications》1985,132(2):490-496
Immunoblotting of plasma membrane fractions from rat kidney cortex with antibody to human erythrocyte glucose transporter showed a single major cross-reacting material of 48K in basolateral membrane fractions possessing a facilitated diffusion system for D-glucose, but not in brush border membrane fractions which have a Na-dependent active transport system. Cytochalasin B inhibited D-glucose uptake in basolateral membrane vesicles but not in brush border vesicles. Cross-reacting materials of 44-55K were detected in several animal cells exhibiting facilitated diffusion systems, including a hormone dependent system. These results indicate molecular difference between glucose transporters of facilitated diffusion systems and active transport systems. 相似文献
48.
Retarded decline in poly-ADPR content and poly-ADPR synthetase activity in chicken dystrophic muscle
The activity of poly-ADPR synthetase declines just after hatching in normal chick muscle nuclei. However, in dystrophic chick muscle nuclei it decreases 5 weeks after hatching. A delayed decrease in the amount of poly-ADPR is also observed in dystrophic chick muscle nuclei. These observations suggest that dystrophic muscle follows an abnormal developmental program. 相似文献
49.
Relative effectiveness and interaction of ultraviolet-B, red and blue light in anthocyanin synthesis of apple fruit 总被引:3,自引:0,他引:3
The effect of light on anthocyanin production in apple ( Malus pumila Mill. cv. Jonathan) skin disks was investigated, with prolonged irradiation from different light sources. High fluence rates of white light provided from a xenon lamp were unable to produce large amounts of anthocyanin, and anthocyanin production became saturated at about 30 W m−2 . When UV-B light, provided by a fluorescent lamp which had an emission peak at 312 nm, was combined with the white light, anthocyanin production was synergistically stimulated and increased up to the highest fluence rates of white light tested (44 W m−2 ). This UV-B light was more effective than red and blue light provided from fluorescent lamps, but anthocyanin production became saturated at about 1.7 W m−2 . However, simultaneous irradiation with red and UV-B light had a synergistic effect. UV-B light was also effective in increasing anthocyanin production in whole fruit. Therefore this synergism seemed to have an important role in the development of the desirable red skin color under field light conditions. The results of aminoethoxyvinylglycine treatment suggested that ethylene was not involved in the stimulative effect of UV-B light. 相似文献
50.
Fucosylation of membrane proteins in soybean cultured cells : effects of tunicamycin and swainsonine 总被引:3,自引:2,他引:1
Cultures of soybean cells incorporate [5,6-3H]-l-fucose into various cellular components including lipids and proteins. The membrane glyco-proteins were digested with pronase to produce glycopeptides, and the glycopeptides were isolated on columns of Biogel P-4. The major fucoselabeled glycopeptide sized as a Hexose15-17-N-acetylglucosamine2 (GlcNAc2) on columns of Biogel P-4. Fucose incorporation was also examined in the presence of the processing inhibitor swainsonine, and the glycosylation inhibitor tunicamycin. In the presence of swainsonine, the incorporation of fucose was not reduced but the glycopeptides were smaller in size and migrated like Hexose12-13-GlcNAc2 structures. On the other hand, tunicamycin inhibited the incorporation of fucose into the glycopeptides by 70 to 80%, indicating that the l-fucose was present in N-linked oligosaccharides. 相似文献