A 15N-1H nuclear magnetic resonance study on the interaction between isoleucine tRNA and isoleucyl-tRNA synthetase from Escherichia coli.
Imino 15N and 1H resonances of Escherichia coli tRNA(lIle) were observed in the absence and presence of E coli isoleucyl-tRNA synthetase. Upon complex formation of tRNA(lIle) with isoleucyl-tRNA synthetase, some imino 15N-1H resonances disappeared, and some others were significantly broadened and/or shifted in the 1H chemical shift, while the others were observed at the same 15N-1H chemical shifts. It was indicated that the binding of tRNA(lIle) with IleRS affect the following four regions: the anticodon stem, the junction of the acceptor and T stems, the middle of the D stem, and the region where the tertiary base pair connects the T, D, and extra loops. This result is consistent with those of chemical footprinting and site-directed mutagenesis studies. Taken together, these three independent results reveal the recognition mechanism of tRNA(lIle) by IleRS: IleRS recognizes all the identity determinants distributed throughout the tRNA(lIle) molecule, which induces changes in the secondary and tertiary structures of tRNA(lIle).
Niimi
T
T
Department of Biophysics and Biochemistry, Graduate School of Science, University of Tokyo, Japan.
Kawai
G
G
Takayanagi
M
M
Noguchi
T
T
Hayashi
N
N
Kohno
T
T
Muto
Y
Y
Watanabe
K
K
Miyazawa
T
T
Yokoyama
S
S
D001483:Base Sequence; D001665:Binding Sites; D004926:Escherichia coli / Q000201:enzymology*; D007533:Isoleucine-tRNA Ligase / Q000737:chemistry* / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012355:RNA, Transfer, Ile / Q000737:chemistry* / Q000378:metabolism
D012355:RNA, Transfer, Ile; D007533:Isoleucine-tRNA Ligase