Open AccessEscherichia coli ribosomal protein S1 has two polynucleotide binding sites.
Author(s) -
David E. Draper,
Charlotte W. Pratt,
Peter H. von Hippel
Publication year - 1977
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.74.11.4786
Subject(s) - polynucleotide , dna , cytidine , biochemistry , escherichia coli , rna , nucleic acid , binding site , biology , microbiology and biotechnology , chemistry , enzyme , gene
The interaction of Escherichia coli ribosomal protein S1 with a variety of RNA and DNA oligomers and polymers has been studied, using both a sedimentation technique and the quenching of intrinsic protein fluorescence upon nucleic acid binding to obtain equilibrium binding parameters. Two polynucleotide binding sites have been detected on S1: site I binds either single-stranded DNA or RNA and does not discriminate between adenine- and cytidine-containing polynucleotides, while the II binding is highly specific for RNA over DNA and shows a marked preference for cytidine polynucleotides over the corresponding adenine-containing species. On the basis of the binding properties of S1 to denatured DNA cellulose and poly(rC)-cellulose, it is demonstrated that every S1 molecule carries both a site I and a site II. Some possible implications of these results for mechanisms of protein synthesis and phage Qbeta replication are briefly considered.