Grankowski N, Gasior E, Issinger O G
Department of Molecular Biology, Maria Curie-Skłodowska University, Lublin, Poland.
Biochim Biophys Acta. 1993 Oct 3;1158(2):194-6. doi: 10.1016/0304-4165(93)90014-y.
Kinetic studies on the 60S protein kinase were conducted with synthetic peptides and ribosomal proteins as substrate. Peptide RRREEESDDD proved to be the best synthetic substrate for this enzyme. The peptide has a sequence of amino acids which most closely resembles the structure of potential phosphorylation sites in natural substrates, i.e., acidic ribosomal proteins. The superiority of certain kinetic parameters for 60S kinase obtained with the native whole 80S ribosomes over those of the isolated fraction of acidic ribosomal proteins indicates that the affinity of 60S kinase to the specific protein substrate not only depends on the structure of the polypeptide chain around the target amino acid but also on its native structure within the 80S ribosome.
以合成肽和核糖体蛋白为底物对60S蛋白激酶进行了动力学研究。肽RRREEESDDD被证明是该酶的最佳合成底物。该肽的氨基酸序列与天然底物（即酸性核糖体蛋白）中潜在磷酸化位点的结构最为相似。用天然完整的80S核糖体获得的60S激酶的某些动力学参数优于酸性核糖体蛋白分离组分的动力学参数，这表明60S激酶对特定蛋白质底物的亲和力不仅取决于靶氨基酸周围多肽链的结构，还取决于其在80S核糖体中的天然结构。
