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11.
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
12.
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
13.
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
14.
Masaki Sugiura Tsutomu Takagi Masahiko Kisumi 《Applied microbiology and biotechnology》1985,21(3-4):213-219
Summary Proline-producing strains of Serratia marcescens Sr41 were constructed by three rounds of mutagenesis. A strain SP103 which did not degrade l-proline carried the putA mutation leading to lack of proline oxidase. A 3,4-dehydroproline-resistant mutant SP105, derived from strain SP103, carried the dpr-1 mutation which resulted in desensitization of the feedback inhibition of glutamate kinase. Strain SP103 produced 5.5 mg of l-proline per ml of fermentation medium containing sucrose and urea. Growth inhibition by proline analogs was enhanced when succinate was used as a carbon source in the medium. A thiazolidine-4-carboxylate-resistant mutant SP126 derived from strain SP105 produced 20.5 mg of l-proline per ml of medium. The mutation carried by strain SP126 might be distant from dpr-1 and putA mutations on the chromosome. Pyrroline-5-carboxylate reductase was not repressed by proline in S. marcescens Sr41. 相似文献
15.
E Katayama T Wakabayashi F Reinach T Masaki D A Fischman 《Journal of biochemistry》1984,95(3):721-727
MF-18, one of the monoclonal antibodies generated to chicken myosin, cross-reacted with rabbit skeletal myosin subfragment-1 (S1). Utilizing an improved procedure of immuno-blotting, a decrease in reactivity of MF-18 to S1 by trinitrophenylation was observed. This indicates that the reactive lysyl residue is very close to the hapten site. This is consistent with the evidence that the hapten site resides in the 26,000 dalton tryptic fragment of S1. Use of such antibodies as labels may open the way to determining the location of specific hapten sites in the three-dimensional image of actin-S1 complex reconstructed from the electron micrographs. 相似文献
16.
Differential expression and distribution of chicken skeletal- and smooth-muscle-type alpha-actinins during myogenesis in culture 总被引:13,自引:11,他引:2 下载免费PDF全文
Antibodies to chicken fast skeletal muscle (pectoralis) alpha-actinin and to smooth muscle (gizzard) alpha-actinin were absorbed with opposite antigens by affinity chromatography, and four antibody fractions were thus obtained: common antibodies reactive with both pectoralis and gizzard alpha-actinins ([C]anti-P alpha-An and [C]anti-G alpha-An), antibody specifically reactive with pectoralis alpha-actinin ([S]anti-P alpha-An), and antibody specifically reactive with gizzard alpha-actinin ([S]anti-G alpha-An). In indirect immunofluorescence microscopy, (C)anti-P alpha-An, (S)anti-P alpha-An, and (C)anti-G alpha- An stained Z bands of skeletal muscle myofibrils, whereas (S)anti-G alpha-An did not. Although (S)anti-G alpha-An and two common antibodies stained smooth muscle cells, (S)anti-P alpha-An did not. We used (S)anti-P alpha-An and (S)anti-G alpha-An for immunofluorescence microscopy to investigate the expression and distribution of skeletal- and smooth-muscle-type alpha-actinins during myogenesis of cultured skeletal muscle cells. Skeletal-muscle-type alpha-actinin was found to be absent from myogenic cells before fusion but present in them after fusion, restricted to Z bodies or Z bands. Smooth-muscle-type alpha- actinin was present diffusely in the cytoplasm and on membrane- associated structures of mononucleated and fused myoblasts, and then confined to membrane-associated structures of myotubes. Immunoblotting and peptide mapping by limited proteolysis support the above results that skeletal-muscle-type alpha-actinin appears at the onset of fusion and that smooth-muscle-type alpha-actinin persists throughout the myogenesis. These results indicate (a) that the timing of expression of skeletal-muscle-type alpha-actinin is under regulation coordination with other major skeletal muscle proteins; (b) that, with respect to expression and distribution, skeletal-muscle-type alpha-actinin is closely related to alpha-actin, whereas smooth-muscle-type alpha- actinin is to gamma- and beta-actins; and (c) that skeletal- and smooth- muscle-type alpha-actinins have complementary distribution and do not co-exist in situ. 相似文献
17.
Summary When the red-light grown protonema ofAdiantum capillus-veneris was transferred to the dark, the nucleus ceased its migration ca. 5 hours before cell plate formation (Mineyuki andFuruya 1980). To see whether the nucleus was held by some cytoplasmic structure during nuclear positioning, protonemata were treated with various centrifugal forces at different stages of the cell cycle. Nuclei of G1 phase were easily displaced by centrifugation at 360×g for 15 minutes, but those of G2 or M phase were not displaced by it, suggesting that the nuclei were held by some cytoplasmic elements in G2 or M phase. This nuclear anchoring was not detectable in protonemata that were treated with 5mM colchicine. With this treatment, the nucleus did not stop its migration at late G2 and moved even in prophase. And the retardation of organelle movement which was observed in cytoplasm on the lateral side of the nucleus after the cessation of premitotic nuclear migration (Mineyuki andFuruya 1984) was not observed in the presence of colchicine. Thus the nuclei appear to be held by colchicine-sensitive structure in cytoplasm between the lateral surface of the nucleus and cell wall during the premitotic nuclear positioning. Electron micrographs showing cytoplasmic microtubules were consistent with the idea.Abbreviations PPN
Premitotic positioning of the nucleus
- L region
Cytoplasm between the lateral surface of the nucleus and cell wall (seeMineyuki
et al. 1984) 相似文献
18.
Differentiation of myosin in chick embryos 总被引:14,自引:0,他引:14
19.
20.
The effect of an analog of LH-RH, (Des-Gly-NH210, Proethylamide9)-LH-RH, on LH release, was studied in one bull with azooapermia, and one cow with cystic follicle. The single intravenous injection of 100 μg LH-RH analog caused abrupt and marked increase in serum LH and the high levels of LH were maintained for 3 hours. The highest levels of serum LH were 48 and 114 times as high as the pre-treatment levels in a bull and a cow, respectively. Further studies are being undertaken to evaluate this compound for improving reproductive function in cattle. 相似文献