title: Ribosomes from Xenopus laevis ovaries and the polyuridylic acid-directed biosynthesis of polyphenylalanine.
abstract: Single ribosomes account for 90% or more of the ribosome fraction of Xenopus laevis ovaries. These ribosomes have low endogenous activity in a cell-free protein-synthesizing system but synthesize polyphenylalanine in the presence of poly U under conditions comparable with those reported for mammalian or bacterial systems. These observations agree with the view that the ribosome is deficient in mRNA.
mesh_terms: D000818:Animals; D001001:Anura; D005260:Female; D066298:In Vitro Techniques; D008274:Magnesium / Q000494:pharmacology; D010053:Ovary / Q000378:metabolism; D010452:Peptide Biosynthesis; D010649:Phenylalanine / Q000378:metabolism*; D011119:Polynucleotides; D011189:Potassium Chloride; D012333:RNA, Messenger / Q000378:metabolism; D011817:Rabbits; D012156:Reticulocytes / Q000201:enzymology; D012270:Ribosomes / Q000378:metabolism*; D013696:Temperature; D014500:Uracil Nucleotides
chemical_list: D011119:Polynucleotides; D012333:RNA, Messenger; D014500:Uracil Nucleotides; D010649:Phenylalanine; D011189:Potassium Chloride; D008274:Magnesium