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We describe a method for determining the torsion angle ϕ in peptides. The technique is based on the measurement of the relative orientation of the N−H^N and C^α−H^α bonds, which is manifested in the rotational sideband spectrum of the sum and difference of the two corresponding dipolar couplings. The method exploits ¹⁵N−¹³C double-quantum and zero-quantum coherences, which evolve simultaneously under the N−H and C−H dipolar interactions. The magnitudes of these dipolar couplings scaled by the proton homonuclear decoupling sequence are directly extracted from control experiments that correlate the dipolar interactions with the isotropic chemical shifts. Applied to ¹⁵N-labeled N-acetyl-d,l-valine, the experiment yielded ϕ = −135°, which agrees well with the X-ray crystal structure. Simulations indicate that the accuracy of the measured angle ϕ is within ±10° when the N−H^N and C^α−H^α bonds are …