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41.
High-Mr (greater than 2 X 10(6)) hyaluronic acid (about 82 micrograms/ml) was found for the first time in rabbit pericardial fluid. Biosynthetic experiments with minced pericardium from rabbit showed that the high-Mr hyaluronic acid in the pericardial fluid was actively synthesized by the pericardium from [3H]glucosamine. 相似文献
42.
Fractionation of yeast mitochondria by controlled hypotonic treatment revealed that the enzyme for heme attachment to apocytochrome c was localized in mitochondrial inner membrane. Trypsin digestion of mitoplasts resulted in a considerable loss of enzymatic activity, whereas the enzyme in intact mitochondria resisted the digestion. Triton X-100 solubilized the enzyme from the membrane but high concentration of salt did not. These results reveal that the enzyme for heme attachment is localized in mitochondrial inner membrane facing the cytoplasmic surface. 相似文献
43.
Mizukami Hajime; Terao Toshimitsu; Amano Akemi; Ohashi Hiromu 《Plant & cell physiology》1986,27(4):645-650
Cultured cells of Gardenia jasminoides produced both salicinand isosalicin from exogenously supplied salicyl alcohol. Theglucosylation activity of the cells was highest in the exponentialphase of growth and ca. 70% of the added substrate was convertedto the glucosides within 4 days. The rate of glucosylation wasalso dependent on the medium composition such as auxin and sucroseconcentrations. The ratio of salicin to isosalicin formed fromsalicyl alcohol was influenced by the growth stage of the culturedcells. Salicin was converted to isosalicin when exogenouslyadded to the culture. (Received October 11, 1985; Accepted March 10, 1986) 相似文献
44.
An acidic α-D-mannosidase has been isolated from the culture filtrate of a wood-rotting Basidiomycete, Pycnoporus sanguineus and the molecular and enzymatic properties of the enzyme determined. The extracellular mannosidase was homogeneous on PAGE at pH 9.4. The Mr as determined by SDS-polyacrylamide disc gel electrophoresis was 64000, and the pI was pH 4.7 using electrofocusing. The purified enzyme had a pH optimum of 4.5 with Baker's yeast mannan and had no activity towards p-nitrophenyl-α-mannoside. The Km and kcat values for Manα1-2Man at pH 4.5 and 30° were 0.9 mM and 1.9 sec. the enzyme had no activity towards Manα1-3Manα1-2Man, and it cleaved specifically the 1,2-α-linked side chain of yeast α-mannan, producing free α-D-mannose. 相似文献
45.
Eiji Ichishima Satoshi Hanzawa Masahiko Watanabe Michio Takeuchi 《Current microbiology》1986,13(4):231-235
Five forms of serine proteinase (EC 3.4.21.14) have been purified fromAspergillus sojae. This paper reports heterogeneity of electrophoretic mobilities, isoelectric points, and kinetic parameters of multiple forms of serine proteinase fromAspergillus sojae, including agerelated changes in thek
cat
/K
m
of electrophoretic species. 相似文献
46.
Yoshiya Shigematsu Ken Tsukahara Tomoaki Tanaka Michio Takeuchi Dr. Eiji Ichishima 《Current microbiology》1986,13(1):43-46
The molecular properties, such as molecular weight, N-and C-terminal amino acids, amino acid composition, and circular dichroism, of 1,2--mannosidase isolated from the culture filtrate ofAspergillus saitoi were determined.The enzyme had aK
m of 0.67 mM andk
cat of 1.27/s with mannobiose at pH 50.0 and 30°C. The anomeric configuration of the reaction products of the enzyme was examined by studying the -anomer. A single Manl2Man linkage in intact Taka-amylase A fromAspergillus oryzae was hydrolyzed, producing free mannose. 相似文献
47.
Cytoplasmic free and membrane-bound ribosomes were isolated from bovine adrenal cortex, and characterized. Contributions of free and bound ribosomes to the synthesis of NADPH-adrenodoxin reductase (AdR) and adrenodoxin (Ad) were determined by examining the presence of their nascent peptides on isolated ribosomes. Nascent peptides were released from the ribosomes by [3H]puromycin in a high salt buffer in the presence of a detergent, and the nascent peptides of AdR and Ad were separately isolated by immunoprecipitation using antibodies. AdR nascent peptides were associated with free and loosely-bound ribosomes, whereas Ad nascent peptides were associated with free, loosely-bound and tightly-bound ribosomes. Smaller nascent peptides of AdR were carried by free ribosomes, whereas larger nascent peptides were preferentially carried by loosely-bound ribosomes. In the case of Ad, smaller nascent peptides were more abundant in free ribosomes than in bound ribosomes. The nascent peptides of Ad were released from bound ribosomes of rough microsomes to the aqueous milieu by puromycin treatment, suggesting the release of completed Ad peptides into the cytoplasm in cells. 相似文献
48.
49.
Noriaki Inamura Saburo Sone Akio Okubo Eiji Kunishige Mie Nakanishi Takeshi Ogura 《Cancer immunology, immunotherapy : CII》1989,28(3):164-170
Summary Human blood monocytes were isolated by counter-flow centrifugal elutriation from healthy donors and these noncytotoxic monocytes were rendered tumoricidal to allogeneic melanoma (A375) cells by activation with a synthetic acyltripeptide (FK-565), as assessed by measuring release of [125I]iododeoxyuridine in 72 h. When monocytes were treated with FK-565 for 16 h, and then fixed with paraformaldehyde, they showed cytotoxicity to A375 melanoma cells. The fixed-monocyte-mediated cytotoxicity to A375 cells was induced by the synergistic actions of FK-565 and recombinant interferon- (rIFN-), but not other cytokines [rIFN-A, rIFN-, tumor necrosis factor (TNF), interleukin (IL)-2, -3 and -6]. For synergistic activation of monocytes with induction of a membrane-associated antitumor monokine, the monocytes had to be incubated first with rIFN- and then with FK-565. FK-565 also acted synergistically with rIFN- to stimulate monocytes to produce membrane-associated IL-1 activity, which induced C3H/HeJ thymocyte blastogenesis in response to phytohemagglutinin P. The tumoricidal and thymocytestimulating activities of the fixed monocytes were almost completely inhibited by a specific anti-(IL-1) antiserum, but not by a specific anti-(IL-1) antiserum or monoclonal anti-TNF antibody. These results suggest that membrane-associated IL-1 of human blood monocytes can be induced by two activation signals (rIFN- then FK-565) at their suboptimal concentrations.Abbreviations IL
interleukin
- IFN
interferon
- TNF
tumor necrosis factor 相似文献
50.
Chronopharmacological study of furosemide; (VI). Influence of prolonged exposure to continuous light
We have previously reported that a time-dependent variability is observed in the diuretic effects of furosemide in rats. The present study was undertaken to examine the influence of prolonged exposure to continuous light on chronopharmacological profiles of furosemide in Wistar rats. In study I, rats were maintained for more than 2 weeks under conditions of light (0700-1900 hrs) and dark (1900-0700 hrs) (L-D). Furosemide (30 mg/kg) was orally given at 1200 hrs or at 2400 hrs. Urine was collected for 8 hours after the drug and urinary excretion of sodium and furosemide were determined respectively. Thereafter, these rats were exposed to continuous light (L-L) for the next 4 weeks, and were again maintained under the L-D cycle. The identical trial of study I was repeated at the end of the L-L (study II) and the second L-D (study III) conditions. Urine volume and urinary excretion of sodium and furosemide following the drug were significantly greater at 1200 hrs than at 2400 hrs under conditions of L-D (study I and III). However these administration time-dependent changes in the effects of furosemide and its urinary amount disappeared with L-L condition (study II). These findings indicate that the mode of the time-dependent changes in the effects of furosemide is altered by prolonged exposure to continuous light. 相似文献