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1.
Staphylococcal gamma-hemolysin and leukocidin are bi-component cytolysins, consisting of LukF (or Hlg1)/Hlg2 and LukF/LukS, respectively. Here, we purified serum inhibitors of gamma-hemolysin and leukocidin from human plasma. Protein sequencing showed that the purified inhibitors of 62, 57, 50 and 38 kDa were the vitronectin fragments with truncation(s) of the C-terminal or both N- and C-terminal regions. The purified vitronectin fragments specifically bound to the Hlg2 component of gamma-hemolysin and the LukS component of leukocidin to form high-molecular-weight complexes with them, leading to inhibition of the toxin-induced lysis of human erythrocytes and human polymorphonuclear leukocytes, respectively. Intact vitronectin also showed inhibitory activity to the toxins. The ability of gamma-hemolysin and leukocidin to bind vitronectin and its fragments is a novel function of the pore-forming cytolysins. 相似文献
2.
Summary An activated carbon column was utilized for the synthesis of disaccharides by use of a reversed hydrolysis activity of an immobilized -galactosidase column in order to shift the equilibrium to the direction of condensation. The yields of lactulose and allo-lactulose from galactose and fructose, and N-acetyl lactosamine and N-acetyl allolactosamine from galactose and N-acetyl glucosamine, were 11.3% and 10.0%, respectively. 相似文献
3.
K Sakai T Kobayashi T Komuro S Nakamura K Mizuta Y Sakanoue E Hashimoto H Yamamura 《Biochemistry international》1987,14(1):63-70
Phosphorylation of clupeine sulfate by purified rat brain calcium-activated, phospholipid-dependent protein kinase (protein kinase C) was studied. In the absence of Ca2+, phosphatidylserine and diolein markedly stimulated its phosphorylation. However Ca2+ did not stimulate but inhibit this phosphorylation about 30% in the presence of phospholipids. Random polymer (Arg, Ser) 3:1 and (Lys, Ser) 3:1 could be phosphorylated by protein kinase C. In the presence of phospholipids Ca2+ is not needed for the phosphorylation of polymer (Arg, Ser) 3:1, while Ca2+ is necessary for polymer (Lys, Ser) 3:1. Non-requirement of Ca2+ on clupeine phosphorylation by protein kinase C is briefly discussed. 相似文献
4.
Modification in Cell Shape Unrelated to Cellulose Microfibril Orientation in Growing Thallus Cells of Chaetomorpha moniligera 总被引:1,自引:0,他引:1
Cellulose microfibril orientation patterns in thallus cellsof Chaetomorpha moniligera were studied, and the relationshipbetween the microfibril and the peripheral microtubule arrangementsduring cell-shape modification by colchicine was examined. Inthe cuttings from growing thalli, linearly arranged cylindricalcells developed into cask-shaped cells during 46 daysof culture at 27?C. In the cylindrical cells, microfibrils formingthe innermost portion of the wall were arranged alternatelyin longitudinal and transverse directions, but peripheral microtubuleswere always arranged only in a longitudinal direction. Thesefeatures were also noted in the cask-shaped cells. Colchicineat 103M and 3?103M accelerated both cell expansionand wall thickening with matrix deposition, but the directionsin which both microfibrils and microtubules were arranged werethe same as those of the cylindrical cells. These results indicatethat (1) the microfibril and microtubule arrangements of Chaetomorphaare not necessarily correlated, (2) changes in cell shape ofChaetomorpha are not necessarily accompanied by changes in thearrangement of cell-wall microfibrils, and (3) colchicine playsa role in the loosening and thickening of cell walls by enhancingmatrix deposition. (Received June 2, 1986; Accepted February 13, 1987) 相似文献
5.
6.
Studies on DNA markers (D4S10 and D4S43/S127) genetically linked to Huntington's disease in Japanese families 总被引:1,自引:0,他引:1
Ichiro Kanazawa Ikuko Kondo Joh-E Ikeda Teruaki Ikeda Yuichior Shizu Mitsuo Yoshida Hirotaro Narabayashi Shigetoshi Kuroda Hisayuki Tsunoda Eiji Mizuta Yoko Okuno Kiyotaka Sugawara Miho Murata Mafuyu Takahashi James F. Gusella 《Human genetics》1990,85(3):257-260
Summary This is the first full report on the genetic linkage between Japanese Huntington's disease and the DNA markers D4S10 and D4S43/S127. With use of the HindIII, BglI, and EcoRI polymorphisms detected at D4S10, and the combination of all these polymorphisms to give composite haplotypes, nine Japanese Huntington's disease families were found to be informative. Three recombinants for D4S10 were detected in these families, giving a maximum lod score of 1.662 at a of 0.10. Similarly, when we used the MspI and PvuII polymorphisms detected by D4S43/S127, five families gave informative results. No recombinant was detected in these families, giving a maximum lod score of 3.348 at a of 0.00. These results clearly support the view that the Japanese Huntington's disease gene may be identical with the Western gene, in spite of the lower prevalence rate in Japan. 相似文献
7.
Katsumi Togashi 《Population Ecology》1988,30(2):177-192
Summary The seasonal occurrence ofMonochamus alternatus and newly weakened trees were investigated in aPinus thunbergii stand for 4 years. Adult beetles were present between June and September with a peak in their population occurring in early
July followed by a decline then a period of about one month being in a steady number. The average number ofBursaphelenchus xylophilus (Nematoda), which is the causal agent of pine wilt disease, within beetles decreased as the season advanced. Pine trees newly
weakened byB. xylophilus appeared between June and October, especially from August to October. The proportion of weakened or killed trees was directly
proportional to the average beetle density per tree from June to August. 相似文献
8.
One of the human urinary ribonucleases (RNases) was isolated and purified to homogeneity (SDS-PAGE) by means of a series of column chromatographies. The enzyme, designated RNase 1, is a glycoprotein with a molecular weight of approximately 16,000. Rabbit antibody to the purified RNase 1 reacted with human urine and sera, as well as with the purified RNase 1. The genetic polymorphism of serum RNase 1 was studied by polyacrylamide gel isoelectric focusing (IEF-PAGE) in a pH range of 5-8, followed by immunoblotting with antisera specific for RNase 1. Two common phenotypes, RNASE1 1 and RNASE1 1-2, were easily recognized. The homogeneous phenotype, RNASE1 1, consisted of four major bands with different pI values, and the heterogeneous phenotype, RNASE1 1-2, was presumed to represent a mixture of each of the homogeneous phenotypes 1 and 2; however, the other homogeneous phenotype, RNASE1 2, was not detected in our samples. Family studies are in agreement with an autosomal codominant transmission of the two alleles. Population studies indicate that the frequencies of the RNASE 1 and RNASE1 2 alleles are .988 and .012, respectively. 相似文献
9.
Protease-activated protein kinase in rat liver plasma membrane 总被引:3,自引:0,他引:3
E Hashimoto K Mizuta H Yamamura 《Biochemical and biophysical research communications》1985,131(1):246-254
Upon limited proteolysis with trypsin, a cAMP and Ca2+-independent protein kinase was produced from rat liver plasma membrane. This enzyme showed a multifunctional capacity and phosphorylated calf thymus histone and rat liver ribosomal proteins. The molecular weight was estimated to be 5.0 X 10(4). When plasma membrane was treated with a buffer containing Triton X-100, a proenzyme with a molecular weight of 8.4 X 10(4) was extracted. By tryptic digestion, the proenzyme was converted to an active protein kinase which was similar to the enzyme obtained by the direct digestion of membrane. However, this proenzyme phosphorylated H1 histone in the presence of Ca2+ and phospholipid without proteolytic digestion. These results indicate the existence of a protease-activated protein kinase in rat liver plasma membrane and the proenzyme seems to be same as protein kinase C. 相似文献
10.
A Tsutou S Nakamura A Negami K Mizuta E Hashimoto H Yamamura 《Biochemical and biophysical research communications》1985,126(1):544-550
Porcine uterine smooth muscle phosphorylase kinase has been partially purified. The enzyme was activated about 1.5-2.0-fold by exogenous calmodulin. Half maximal stimulation was observed at about 100 nM calmodulin. The activation was dependent on calcium and was maximum at pH 7.5 in the range of pH from 6 to 9. This activation was completely abolished by 100 microM trifluoperazine. The result suggested that unlike slow and cardiac muscles, phosphorylase kinase of uterine smooth muscle showed similar response to calmodulin with that of fast muscle. The physiological role of the calcium and calmodulin-dependent activation of myometrium phosphorylase kinase is briefly discussed. 相似文献