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991.
Purification and immunological characterization of a new form of gamma-glutamyltransferase of human semen. 总被引:1,自引:0,他引:1
A new form of gamma-glutamyltransferase was purified from human seminal plasma. The purified enzyme was composed of two non-identical subunits with apparent molecular masses of 150 and 95 kDa on polyacrylamide gel electrophoresis (PAGE) in the presence of sodium dodecyl sulfate (SDS), and showed a molecular mass of 500 and 250 kDa on gel filtration in the absence and presence of 1% Triton X-100, respectively. This enzyme was different from human renal gamma-glutamyltransferase not only in apparent molecular masses, but also in amino acid compositions of both the subunits to each other. Experiments with the antisera raised against the purified enzyme revealed that the enzyme was different from the renal, hepatic and testicular enzymes in reactivity to the antibody though partially related to those enzymes. Ouchterlony double diffusion analysis indicated that both human seminal plasma and prostatic extract contained two types of gamma-glutamyltransferase, one is that we purified and the other the renal type. Hence, it is most likely that gamma-glutamyltransferase accounting for most of the enzyme activity in semen results from prostata followed by secretion to seminal plasma. 相似文献
992.
Isolation of three forms of cystatin from submandibular saliva of isoproterenol-treated rats, its properties and kinetic data 总被引:1,自引:0,他引:1
Three rat salivary cystatins (designated as RSC-1, RSC-2 and RSC-3) induced by chronic isoproterenol (IPR) treatment, but not detected in normal rats, were purified from submandibular saliva of chronically IPR-treated rats by Mono-Q, hydroxyapatite and TSKgel Phenyl-5PW chromatographies. Their molecular weights (Mr) and isoelectric points (pI) differed from each other as follows: RSC-1 (Mr 16,500, pI 4.4), RSC-2 (Mr 15,500, pI 4.4) and RSC-3 (Mr 14,500, pI 4.5). The amino acid compositions of these inhibitors were very similar and the three forms showed complete immunological identity in a double immunodiffusion system. The partial amino acid sequence results showed that these inhibitors belonged to family 2 of the cystatin superfamily. These three forms strongly inhibited the enzyme activities of ficin and papain, but not of cathepsin B and trypsin. The inhibition constants (Ki) of RSC-1, RSC-2 and RSC-3 for ficin were 0.19, 0.50 and 0.012 nM, and for papain were 1.5, 0.93 and 0.03 nM, respectively. RSC-3 inhibited ficin and papain more strongly than did RSC-1 and RSC-2. 相似文献
993.
Yasuhiro Hashimoto Mikiko Abe Akemi Suzuki Kentaro Iwasaki Tamio Yamakawa 《Glycoconjugate journal》1985,2(3-4):255-265
Genetic polymorphism in the expression of the GM1(NeuGc) ganglioside has been shown in the liver of inbred strains of mice. Through analysis of the gangliosides of H-2 congenic and recombinant strains, this polymorphism was demonstrated to be controlled by a locus mapped left outside of the H-2 complex on chromosome 17, and the locus was assumed to control the level of the activity of GM1(NeuGc) synthetase, UDP-galactose:GM2(NeuGc) galactosyltransferase (E.C.2.4.1.62) [Hashimotoet al., J Biochem (1983) 94:2049-54].In the present study we analyzed the genetic linkage between the activity of the galactosyltransferase and the H-2 haplotype. For this purpose, we selected two inbred strains of mice, WHT/Ht and BALB/c, because they have different levels of the transferase activity and show different H-2 haplotypes; the specific activity of the transferase obtained with BALB/c was one-eighth of that with WHT/Ht, and BALB/c expressed the la.7 antigen as one of the products encoded in their H-2d complex, whereas WHT/Ht did not. To analyze the linkage between these two phenotypes, WHT/Ht were mated with BALB/c to obtain the F1 mice, and the female F1 mice were then backcrossed to WHT/Ht. It was found that one half of the backcross generation expressed the la.7 antigen derived from BALB/c and had a significantly lower specific activity of the transferase than that of WHT/Ht, while the other half did not express the la.7 antigen but had the same specific activity of the transferase as that obtained with WHT/Ht.These results suggest that the locus controlling the level of the transferase activity in mouse liver is linked to the H-2 complex on chromosome 17.Abbreviations NeuGc
N-glycolylneuraminic acid
The ganglioside nomenclature is based on the system of Svennerholm, J Neurochem (1963) 10:613-23. The sialic acid species present is shown in parentheses after the ganglioside abbreviation. 相似文献
994.
Leukotriene B4 receptor 2 regulates the proliferation,migration, and barrier integrity of bronchial epithelial cells
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995.
Yuri Miura Noritaka Hashii Yuki Ohta Yoko Itakura Hiroki Tsumoto Junya Suzuki Daisuke Takakura Yukiko Abe Yasumichi Arai Masashi Toyoda Nana Kawasaki Nobuyoshi Hirose Tamao Endo 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(6):1462-1471
Background
Glycosylation is highly susceptible to changes of the physiological conditions, and accordingly, is a potential biomarker associated with several diseases and/or longevity. Semi-supercentenarians (SSCs; older than 105?years) are thought to be a model of human longevity. Thus, we performed glycoproteomics using plasma samples of SSCs, and identified proteins and conjugated N-glycans that are characteristic of extreme human longevity.Methods
Plasma proteins from Japanese semi-supercentenarians (SSCs, 106–109?years), aged controls (70–88?years), and young controls (20–38?years) were analysed by using lectin microarrays and liquid chromatography/mass spectrometry (LC/MS). Peak area ratios of glycopeptides to corresponding normalising peptides were subjected to orthogonal projections to latent structures discriminant analysis (OPLS-DA). Furthermore, plasma levels of clinical biomarkers were measured.Results
We found two lectins such as Phaseolus vulgaris, and Erythrina cristagalli (ECA), of which protein binding were characteristically increased in SSCs. Peak area ratios of ECA-enriched glycopeptides were successfully discriminated between SSCs and controls using OPLS-DA, and indicated that tri-antennary and sialylated N-glycans of haptoglobin at Asn207 and Asn211 sites were characterized in SSCs. Sialylated glycans of haptoglobin are a potential biomarker of several diseases, such as hepatocellular carcinoma, liver cirrhosis, and IgA-nephritis. However, the SSCs analysed here did not suffer from these diseases.Conclusions
Tri-antennary and sialylated N-glycans on haptoglobin at the Asn207 and Asn211 sites were abundant in SSCs and characteristic of extreme human longevity.General significance
We found abundant glycans in SSCs, which may be associated with human longevity. 相似文献996.
997.
Advanced glycation end‐products and Porphyromonas gingivalis lipopolysaccharide increase calprotectin expression in human gingival epithelial cells
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998.
999.
The banker plant system has been introduced for the biological control of various pest species in Japanese greenhouses. With the banker plant system, non-crop plants infested with a host insect (a non-commercial crop pest) are placed in the greenhouse to provide alternative resources for the parasitoids or predators. We want to evaluate the effectiveness for controlling pests on the crop in a quantitative way by immigrating predators from the banker plant. Therefore, we developed a simple model for the interaction of the pest and predator in the crop and included the banker plant only as a source for predators. For three different pest-predator systems we parameterised the model and used these models to predict under what conditions biological control in a banker plant system is successful. We defined successful as keeping the pest below the economic injury level of the crop estimated from damage analysis. Because the crop is mostly grown during a period that lasts less than a year our analysis should not only focus on the equilibrium dynamics. In contrast, it should also focus on the transient dynamics. Our main analytical result, from the equilibrium analysis, is that for successful control the maximum lifetime consumption of immigrating predators should exceed the daily prey growth at half the value of the maximum consumption rate. For practical purpose this translates into the fact that the immigration of predators at a low initial pest density is crucial for successful control. 相似文献
1000.
We detected lectin-like compounds and lectin receptors in microalgae by hemagglutination, competitive inhibition with sugars, and reactivity with lectins isolated from other sources. Cell extracts from eight species of Dinophyceae and from one species each of Raphidophyceae and Bacillariophyceae exhibited hemagglutination toward trypsinized rabbit erythrocytes. In addition, the culture media of the dinoflagellate Alexandrium cohorticula and the raphidophyte Chattonella antiqua displayed similar hemagglutination. These activities were not inhibited by any monosaccharides or oligosaccharides tested but were inhibited by some specific glycoproteins. This suggests that the active factors were lectin-like compounds. Upon exposing intact, healthy cells of 12 species of Dinophyceae and one species each of Raphidophyceae, Cryptophyceae, Bacillariophyceae, and Chlorophyceae to lectins isolated from either macroalgae or terrestrial plants, most species were adversely affected. The negative effects included one or more of the following: impaired motility, disappearance of motility, agglutination, abnormal morphology, and cell rupture or lysis. Some species, even after freezing, thawing, and washing with saline solution, still agglutinated with macroalgal or terrestrial plant lectins. This study suggests that lectins and carbohydrate-containing lectin receptors may commonly occur on the cell surfaces of various species of microalgae. 相似文献