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621.
Sheep liver cytosol (105,000 X g supernatant) yields two major peaks of protein kinase by using DEAE-Trisacryl M as an ion-exchange resin at pH 7.0. Peak I (Type-I), corresponding to 30-50% of the total activity, is not retained by the column at a starting ionic strength of ca. 0.06 M, while Peak-II (Type-II) is eluting at 0.17 M ionic strength. Both peaks are found to be dependent on cAMP and are active on histone (ATP: Protein phosphotransferase, EC 2.7.1.37). Kms apparents for histone and ATP are 1.5 +/- 0.5 mg/ml and 16 +/- 4 microM, respectively, for PrK-I while that of PrK-II are 1.8 mg/ml and 28.6 microM, respectively. Both enzymes are found to be stable for two weeks at 4 degrees C. Molecular weight determination of crude extract (105,000 X g supernatant) show three peaks corresponding to the molecular weights of 251,000; 131,800 and 43,600.  相似文献   
622.
623.

The scientific interest in developing new complexes as inhibitors of bacterial biofilm related infections is constantly rising. The present work describes the chemical synthesis, structural and biological scrutiny of a triazole Schiff base ligand and its corresponding complexes. Triazole Schiff base, (2-methoxy-4-[(1H-1,2,4-triazol-3-ylimino)methyl]phenol) was synthesized from the condensation reaction of 3-amino-1,2,4-triazole and 4-hydroxy-3-methoxybenzaldehyde in an equimolar ratio. The triazole ligand (H2L) was characterized by physical (solubility, color, melting point), spectroscopic [UV–visible (UV–Vis), Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (1H-NMR) and mass spectra (MS)] and micro analysis to evaluate their elemental composition. The bidentate ligand was complexed with transition metal [VO(IV), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)] in 1:2 molar ratio. The complexes were characterized by physical (color, solubility, decomposition temperature, conductance and magnetic moment), FT-IR, UV–Vis and elemental analysis. Thermal stability and fluorescence properties of the compounds were also determined. Density functional theory based theoretical calculations were accomplished to gain more insight into spectroscopic properties. The frontier molecular orbital analysis revealed that the ligand was less reactive with reduced electron donating capability and more kinetic stability than complexes. The as-synthesized compounds were scrutinized for anti-bacterial and anti-fungal activity against selected strains. Cobalt complex exhibited highest antibacterial activity against Escherichia coli and nickel complex has shown highest antifungal activity against Aspergillus niger. All the compounds also showed good antioxidant activity. The theoretical results reflect consistency with the experimental findings signifying that such compounds could be the promising chemical scaffolds in the near future against microbial infectious.

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624.
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