The 26-subunit, 1.2 MDa human Mediator complex is essential for expression of perhaps all protein-coding genes. Activator binding triggers major structural shifts within Mediator, suggesting a straightforward means to spatially and temporally regulate Mediator activity. By using mass spectrometry (MudPIT) and other techniques, we have compared the subunit composition of Mediator in three differ...

Purification of pea (Pisum sativum) seedling NAD kinase by DEAE-cellulose column chromatography resulted in loss of activity, due to dissociation of an activator from the enzyme. The purified enzyme preparation, which was almost completely inactive, regained the activity when the activator was added back.The activator was purified 320-fold by ion exchange chromatographies. The activator was sus...

largely freed of the protein activator, possess low enzyme activity which is independent of Ca”+. Addition of excess protein activator stimulates the enzyme activity 6to lofold. This activation by the protein activator is shown to be completely dependent on the presence of low concentrations of Ca2+. The concentration of Ca?+ required to give 50% of the maximal activation is 2.3 NM. An equilibr...

An activator of the clathrin-coated vesicle proton translocating ATPase has been purified 1600-fold from bovine brain. The activator, which requires detergent (polyoxyethylene 9-lauryl ether) for release from clathrin-coated vesicles, is heat-stable, trypsin-sensitive, and has an apparent molecular mass of about 6 kDa as determined by high performance liquid chromatography. The activator stimul...

In this study, activator, metakaolin, and silica fume were used as a compound activator to improve the activity of steel slag powder. The influence powder, on resulting strength cement mortar was investigated by orthogonal experiments. For four weight fractions powder (10%, 20%, 30%, 40%), experimental results indicate that compressive can reach up more than 85% control group while flexural 90%...

A protein activator of cyclic 3’:5’-nucleotide phosphodiesterase from bovine brain has been purified to homogeneity by the criteria of analytical polyacrylamide gel electrophoresis, polyacrylamide gel isoelectric focusing, Sephadex G-100 column chromatography, and analytical ultracentrifugation. The over-all purification was about 1700-fold with a yield of 7%. The molecular weight of the activa...