Abstract
Pb2+ ions in sub-millimolar concentrations are known to cleave internucleotide bonds of phenylalanine-specific transfer RNA (tRNA(Phe)) from Saccharomyces. cerevisiae specifically between nucleotides D17 and G18 in the D-loop, with additional minor cleavages after D16 and G15. This makes lead(II) a sensitive structural probe for correct folding of tRNA(Phe). In the present paper we use Pb2+ ions as a functional probe to determine whether this part of tRNA is protected by the Escherichia coli elongation factor EF-Tu in the ternary complex formed between Phe-tRNA(Phe) and EF-Tu.GTP. Our results show that for tRNA in complex with EF-Tu:GTP, the phosphodiester bond after D17 is cleaved, yet the phosphodiester bonds after D16 and G15 are not. To our knowledge, this is the first time that Pb2+ ions, bound at a specific site in tRNA, have been used both to investigate the correct folding of tRNA in complex, and to footprint a functional complex with components whose individual structures are known.
Original language | English |
---|---|
Journal | Biochemistry and Molecular Biology International |
Volume | 31 |
Issue | 1 |
Pages (from-to) | 95-103 |
Number of pages | 9 |
ISSN | 0158-5231 |
Publication status | Published - 1 Jan 1993 |