The 2D [31P] spin-echo-difference constant-time [13C, 1H]-HMQC experiment for simultaneous determination of 3J(H3'P) and 3J(C4'P) in 13C-labeled nucleic acids and their protein complexes.
A two-dimensional [31P] spin-echo-difference constant-time [13C, 1H]-HMQC experiment (2D [31P]-sedct-[13C, 1H]-HMQC) is introduced for measurements of 3J(C4'P) and 3J(H3'P) scalar couplings in large 13C-labeled nucleic acids and in DNA-protein complexes. This experiment makes use of the fact that 1H-13C multiple-quantum coherences in macromolecules relax more slowly than the corresponding 13C single-quantum coherences. 3J(C4'P) and 3J(H3'P) are related via Karplus-type functions with the phosphodiester torsion angles beta and epsilon, respectively, and their experimental assessment therefore contributes to further improved quality of NMR solution structures. Data are presented for a uniformly 13C, 15N-labeled 14-base-pair DNA duplex, both free in solution and in a 17-kDa protein-DNA complex.
Szyperski
T
T
Institut für Molekularbiologie und Biophysik, Eidgenössische Technische Hochschule-Hönggerberg, Zürich, CH-8093, Switzerland.
Fernández
C
C
Ono
A
A
Wüthrich
K
K
Kainosho
M
M
D002244:Carbon / Q000737:chemistry; D002247:Carbon Isotopes; D004247:DNA / Q000737:chemistry; D006801:Humans; D006859:Hydrogen / Q000737:chemistry; D006860:Hydrogen Bonding; D046911:Macromolecular Substances; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D009696:Nucleic Acids / Q000737:chemistry*; D009711:Nucleotides / Q000737:chemistry; D010759:Phosphorus Isotopes; D011506:Proteins / Q000737:chemistry*; D013997:Time Factors
D002247:Carbon Isotopes; D046911:Macromolecular Substances; D009696:Nucleic Acids; D009711:Nucleotides; D010759:Phosphorus Isotopes; D011506:Proteins; D002244:Carbon; D006859:Hydrogen; D004247:DNA