The acidic ribosomal proteins of different yeast species. Phosphorylation by ribosome-associated protein kinases.
Two major ribosomal proteins of Mr 13 kDa and 38 kDa were identified as phosphorylation substrates for ribosome-bound protein kinases from different yeast species. The phosphorylation level was much higher in ribosomes from the cells collected at the exponential growth phase, than in those from the stationary phase. Isoelectrofocusing of the protein band of 13 kDa and subsequent silver staining allowed to identify from four in the case of Pichia stipitis up to ten in Saccharomyces cerevisiae. Saccharomycodes Ludwigii, Torulopsis utilis and Kloeckera apiculata individual peptides. In the most of the yeast species studies five phosphorylated peptides were observed. However, only one or two such phosphopeptides were detected in Pichia stipitis and Trichosporon cutaneum ribosomes, respectively. The same phosphoprotein forms were identified in the in vivo 32P-labelling experiments.
Department of Molecular Biology, Maria Curie-Sklodowska University, Lublin, Poland.
M
M
Cytryńska
I
I
Wojda
T
T
Jakubowicz
D005656:Fungal Proteins / Q000032:analysis*; D010766:Phosphorylation; D011494:Protein Kinases / Q000494:pharmacology*; D012269:Ribosomal Proteins / Q000032:analysis* / Q000378:metabolism; D015003:Yeasts / Q000737:chemistry*
D005656:Fungal Proteins; D012269:Ribosomal Proteins; D011494:Protein Kinases