title: Phosphorylation of elongation factor 1 beta by an endogenous kinase affects its catalytic nucleotide exchange activity.
abstract: Elongation factor 1 beta (EF-1 beta) from Artemia is phosphorylated to a high percentage at serine 89 by an endogenous kinase present in EF-1 beta gamma. Protein sequencing of EF-1 beta revealed that this serine residue is located N-terminally of an acidic cluster of amino acids, (formula; see text) which is critical for casein kinase II-type substrate recognition. A number of compounds known to influence casein kinases were studied, revealing that the kinase activity as present in EF-1 beta gamma belongs to the class of casein kinase II. The rate of nucleotide exchange on EF-1 alpha as catalyzed by EF-1 beta was found to be affected reversibly by the state of phosphorylation of EF-1 beta. In the presence of dephosphorylated EF-1 beta, the exchange rate is almost twice as large compared to the rate in the presence of phosphorylated EF-1 beta. Rephosphorylation of dephosphorylated EF-1 beta diminishes the activity of the protein again. The role of casein kinase II-type enzymes in modulating the function of proteins involved in polypeptide synthesis is discussed.
authors.affiliation: Laboratory for Physiological Chemistry, Sylvius Laboratories, Leiden, The Netherlands.
authors.forename: G M
authors.initials: GM
authors.lastname: Janssen
authors.forename: G D
authors.initials: GD
authors.lastname: Maessen
authors.forename: R
authors.initials: R
authors.lastname: Amons
authors.forename: W
authors.initials: W
authors.lastname: Möller
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001156:Artemia; D007525:Isoelectric Focusing; D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors / Q000378:metabolism*; D010446:Peptide Fragments / Q000032:analysis; D010766:Phosphorylation; D011494:Protein Kinases / Q000378:metabolism*; D014357:Trypsin / Q000378:metabolism
chemical_list: D020648:Peptide Elongation Factor 1; D010445:Peptide Elongation Factors; D010446:Peptide Fragments; D011494:Protein Kinases; D014357:Trypsin