文章基本信息

标题：lac repressor-lac operator interaction: NMR observations
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作者：H Nick ; K Arndt ; F Boschelli 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1982
卷号：79
期号：2
页码：218-222
DOI：10.1073/pnas.79.2.218
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：We show here the changes in the NMR spectra of the Escherichia coli lac repressor when bound to isolated lac operator DNA. The observations focus on the aromatic residues--four tyrosines and a single histidine--in the amino-terminal DNA binding domain of the lac repressor. There is a good correlation between chemical shift changes seen by 19F NMR when compared with 1 H NMR of otherwise identical repressor--DNA complexes. The results suggest that the tyrosines do not intercalate in the DNA. The NMR spectral changes with similarly sized DNA fragments, not containing the lac operator DNA sequence, are different. Thus, the amino-terminal domain of the lac repressor is independently capable of discriminating between lac operator and nonspecific DNA sequences. There can be two amino-terminal fragments per operator in the specific complex.