The primary structure of protein L27 from the peptidyl-tRNA binding site of Escherichia coli ribosomes.
نویسندگان
چکیده
Bromoacetyl-phenylalanyl-tRNA(phe) bound to 70S E. coli ribosomes reacts covalently with proteins of the 50S subunit. The major reactions are with proteins L2 and L27. In the presence of poly(U), 70S-bound bromoacetyl-phenylalanyl-tRNA(phe) can participate in peptidebond formation with phenylalanyl-tRNA(phe) or puromycin. Most of the products of these reactions are also found covalently attached to L2 and L27. Chloramphenicol and sparsomycin markedly inhibit the peptide-bond formation. These results strongly suggest that bromoacetylphenylalanyl-tRNA(phe) can function as a normal peptidyl-tRNA and that the 50S proteins, L2 and L27, are located in the peptidyl-tRNA binding site. The side reactions of bromoacetyl-phenylalanyl-tRNA(phe) are with one or more 50S proteins from the set L14-17, L6 and/or L11, and L26. These occur to a much less extent than the reactions with L2 and L27. Any functional significance of the side reactions is unknown.
منابع مشابه
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عنوان ژورنال:
- Proceedings of the National Academy of Sciences of the United States of America
دوره 70 10 شماره
صفحات -
تاریخ انتشار 1973