Open AccessSequence specific molecular recognition by a monocationic lexitropsin of the decadeoxyribo-nucleotide d-[CATGGCCATGl2: structural and dynamic aspects deduced from high Held1H-NMR studies
Author(s) -
M Lee,
John A. Hartley,
Richard T. Pon,
Krzysztof Krowicki,
J. William Lown
Publication year - 1988
Publication title -
nucleic acids research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 9.008
H-Index - 537
eISSN - 1362-4954
pISSN - 0305-1048
DOI - 10.1093/nar/16.2.665
Subject(s) - sequence (biology) , van der waals force , nucleotide , biology , stereochemistry , crystallography , nuclear magnetic resonance spectroscopy , intramolecular force , base pair , two dimensional nuclear magnetic resonance spectroscopy , nucleic acid sequence , nuclear overhauser effect , base (topology) , dna , molecule , chemistry , biochemistry , mathematical analysis , mathematics , gene , organic chemistry
All 1H-NMR resonances of d-[CATGGCCATG]2 and the 1:1 complex of lexitropsin 1 and the DNA were assigned by the NOE difference, COSY and NOESY methods. Addition of 1 causes the base and imino protons for the sequence 5'-CCAT to undergo the most marked drug-induced chemical shift changes, thereby indicating that 1 is located in this base pair sequence. NOEs confirmed the location and orientation of the drug in the 1:1 complex, with the amino terminus oriented to C(6). The van der Waals interaction between H12a,b of 1 and AH2(8) may be responsible for reading of the 3' A.T base pair in the 5'-CCAT sequence. Exchange NMR effects allow an estimate of approximately equal to 62 s-1 for the intramolecular "slide-swing" exchange of the lexitropsin between two equivalent binding sites with delta G = 58 +/- 5 kJ mol-1 at 301 degrees K.