Biomedical subjects

M Havránek

Publications and source records attributed to M Havránek.

10 recordsLinked to original sources

PubMed1992

Effect of protein phosphorylation on the activity of RNA polymerase in streptomycetes.

RNA polymerase was isolated from Streptomyces granaticolor and protein kinase was partially purified from Streptomyces albus. When RNA polymerase was treated with protein kinase in vitro the activity of RNA polymerase was markedly enhanced. Furthermore, a protein of M = 65 kDa was isolated which, after being phosphorylated, stimulated RNA polymerase activity in vitro. Because neither the beta-subunits nor the alpha-subunits of RNA polymerase were phosphorylated it is assumed that phosphorylation of the 65 kDa protein may regulate the activity of RNA polymerase in streptomycetes.

DNA-Directed RNA Polymerases↗

PubMed1991

Changes of ligand binding after membrane phosphorylation.

Phosphorylation of synaptic plasma brain membranes (SPM) causes a decrease of the specific binding of demethylated tricyclic antidepressants (TCA) and changes the affinity of 3H-imipramine and 3H-desmethylimipramine binding. The decrease of TCA binding was found also in lymphocyte membranes. In platelet membranes a decreased binding was found only with demethylated dibenzazepine derivatives. Bmax and Kd values are also decreased in the presence of phosphatidic acid or alpha-glycerolphosphate.

Animals↗

PubMed1984

CTP can replace GTP in reactions catalyzed by eukaryotic peptide elongation factor 1.

In several reactions catalyzed by highly purified peptide elongation factor 1 from rabbit reticulocytes, GTP may be fully replaced by CTP but not by ATP or UTP. This holds true for the factor-dependent binding of aminoacyl-tRNA to ribosomes, GTPase activity, GTP-dependent autophosphorylation of the factor protein and binding of cholesteryl 14-methylhexadecanoate by the factor.

Adenosine Triphosphate↗

PubMed1983