Location of protein S1 of Escherichia coli ribosomes at the 'A'-site of the codon binding site. Affinity labeling studies with a 3'-modified A-U-G analog.

AUTOR(ES)

Pongs, O

RESUMO

An affinity analog with a 5-bromoacetamido uridine 5'-phosphate moiety bonded to the 3' end of A-U-G has been prepared with the aid of polynucleotide phosphorylase. This 3'-modified, chemically reactive A-U-G analog was used to probe the ribosomal codon binding site. The yield of the reaction depended strongly on the ribosomal source and was sensitive to salt-washing ribosomes. The major crosslinking product was identified to be protein S1. Since the reaction of this 3'-modified A-U-G programmed ribosomes for Met-tRNA-Met-M binding, it is concluded that protein S1 is located at or near the 3'-side of the ribosomal codon binding site.

Documentos Relacionados

• Affinity labeling of the ribosomal decoding site with an AUG-substrate analog.
• Comparison of the reactions of chemically reactive analogs of U-G-A and of A-U-G with ribosomes of Escherichia coli.
• Identification of Chloramphenicol-Binding Protein in Escherichia coli Ribosomes by Affinity Labeling*
• Identification by Photo-Affinity Labeling of the Proteins in Escherichia coli Ribosomes Involved in Elongation Factor G-Dependent GDP Binding
• Electron microscopic visualization of the ATPase site of myosin by photoaffinity labeling with a biotinylated photoreactive ADP analog.