title: A cycloheximide sensitivity factor from yeast required for N-acetylphenylalanylpuromycin formation.
abstract: A protein (factor P) has been isolated from yeast, which was required for sensitivity to cycloheximide of a partially purified polyphenylalanine synthesis system. In the absence of factor P, 10(-3) M cycloheximide was required for 50% inhibition of polyphenylalanine synthesis, while in its presence, 10(-6) M gave 50% inhibition. Coincident with cycloheximide sensitivity was an activity required for EF-2 dependent N-acetylphenylalanylpuromycin (N-AcPhePuro) formation. Transfer of N-AcPhe to puromycin from the tRNA bound in the presence of 26 mM MgCl2 required factor P, as well as EF-2. Studies with antibody against EF-2 demonstrated that P factor was not required during the EF-2 translocation step but for some subsequent step.
mesh_terms: D003513:Cycloheximide / Q000494:pharmacology*; D004352:Drug Resistance, Microbial; D005656:Fungal Proteins / Q000378:metabolism*; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D010441:Peptide Chain Elongation, Translational / Q000187:drug effects; D010445:Peptide Elongation Factors / Q000302:isolation & purification; D010649:Phenylalanine / Q000378:metabolism*; D014176:Protein Biosynthesis / Q000187:drug effects*; D011691:Puromycin / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D010445:Peptide Elongation Factors; D010649:Phenylalanine; D011691:Puromycin; D003513:Cycloheximide; D008274:Magnesium