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991.
Influence of synthetic double-stranded ribonucleic acid (poly I:C) on SV40 viral oncogenesis and transplant tumor in hamsters 总被引:1,自引:0,他引:1
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993.
Purification and characterization of glpQ-encoded glycerophosphodiester phosphodiesterase from Escherichia coli K-12 总被引:3,自引:0,他引:3
Periplasmic glycerophosphodiester phosphodiesterase (EC 3.1.4.2) of Escherichia coli was purified seven-fold to near homogeneity from the cold osmotic shock fraction of a strain harboring a multicopy plasmid carrying the glpQ gene. The enzyme had a minimum subunit molecular weight of 40,000 as assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The native size of the enzyme was 70,000 as assessed by gel filtration chromatography and 75,000 as assessed by nondenaturing gradient polyacrylamide gel electrophoresis, indicating that the native state of the enzyme is dimeric. The enzyme hydrolyzed the deacylation products of all glycerophospholipids tested including glycerophosphocholine, glycerophosphoethanolamine, glycerophosphoglycerol, glycerophosphoinositol, and glycerophosphoserine. The enzyme did not release glycerol or sn-glycerol 3-phosphate from phosphatidyl-DL-glycerol or lysophosphatidyl-DL-glycerol present in Triton X-100 micelles. The enzyme functioned optimally at pH 7.8. The enzyme was totally inactivated by dilution into 1 mM ethylenediaminetetraacetate or ethylene glycol bis(beta-aminoethyl ether)-N,N-tetraacetic acid. Activity was restored by the addition of Ca2+ or Cd2+, and was partially restored by the addition of Mn2+ or Cu2+. Co2+, Mg2+, Zn2+, and Fe2+ did not restore activity. The presence of calcium ions decreased the Km of the enzyme for the substrate, glycerophosphoglycerol, and increased the Vmax. 相似文献
994.
K R Harewood J G Vidrine D L Larson J S Wolff G Schidlovsky S A Mayyasi 《Biochimica et biophysica acta》1973,308(2):252-259
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996.
997.
G. V. Honnappa R. Hannah Sulochana J. Jayaraman 《Journal of bioenergetics and biomembranes》1975,7(4):149-159
Mitochondria were isolated from the muscles ofStreptocephalus dichotomus, Caridina nilotica, Paratelphusa hydrodromous, Sphaerodema rusticum, andEnithares rogersi, all of which belong to the phylum arthropoda, and their properties studied. All mitochondria showed qualitatively similar respiratory and Ca2* uptake capacities but there was much quantitative variation. There emerges an apparent correlation between locomotor activity of the organism and the respiratory activity of the mitochondria. Similar correlation is found between the calcium need of the animal and the Ca2* uptake capacity of the mitochondria. The results also suggest an inverse correlation between respiration and Ca2* uptake. 相似文献
998.
De Vilbiss no. 40 and Vaponefrin standard nebulizers produced aerosols of small particles suitable for deep pulmonary vaccination and therapy of respiratory infections in man and animals. 相似文献
999.
Jiuxing Li Zijie Zhang Jimmy Gu Hannah D Stacey Jann C Ang Alfredo Capretta Carlos D M Filipe Karen L Mossman Cynthia Balion Bruno
J Salena Deborah Yamamura Leyla Soleymani Matthew S Miller John
D Brennan Yingfu Li 《Nucleic acids research》2021,49(13):7267
We performed in vitro selection experiments to identify DNA aptamers for the S1 subunit of the SARS-CoV-2 spike protein (S1 protein). Using a pool of pre-structured random DNA sequences, we obtained over 100 candidate aptamers after 13 cycles of enrichment under progressively more stringent selection pressure. The top 10 sequences all exhibited strong binding to the S1 protein. Two aptamers, named MSA1 (Kd = 1.8 nM) and MSA5 (Kd = 2.7 nM), were assessed for binding to the heat-treated S1 protein, untreated S1 protein spiked into 50% human saliva and the trimeric spike protein of both the wildtype and the B.1.1.7 variant, demonstrating comparable affinities in all cases. MSA1 and MSA5 also recognized the pseudotyped lentivirus of SARS-CoV-2 with respective Kd values of 22.7 pM and 11.8 pM. Secondary structure prediction and sequence truncation experiments revealed that both MSA1 and MSA5 adopted a hairpin structure, which was the motif pre-designed into the original library. A colorimetric sandwich assay was developed using MSA1 as both the recognition element and detection element, which was capable of detecting the pseudotyped lentivirus in 50% saliva with a limit of detection of 400 fM, confirming the potential of these aptamers as diagnostic tools for COVID-19 detection. 相似文献
1000.
MB Donald KX Rodriguez H Shay PW Phuan AS Verkman MJ Kurth 《Bioorganic & medicinal chemistry》2012,20(17):5247-5253
Copper catalyzed azide-alkyne cycloaddition (CuAAC) chemistry is reported for the construction of previously unknown 5-(1H-1,2,3-triazol-1-yl)-4,5'-bithiazoles from 2-bromo-1-(thiazol-5-yl)ethanones. These novel triazolobithiazoles are shown to have cystic fibrosis (CF) corrector activity and, compared to the benchmark bithiazole CF corrector corr-4a, improved logP values (4.5 vs 5.96). 相似文献