Short Sequential and Medium-Range 1H-1H Distance in Polypeptide Secondary Structures

Distance α-helix 310 helix β βp turn Ia turn IIa
dα,N 3.5 3.4 2.2 2.2 3.4

3.2

2.2

3.2

dα,N (i, i+2) 4.4 3.8 - - 3.6 3.3
dα,N (i, i+3) 3.4 3.3 - - 3.1 - 4.2 3.8 - 4.7
dα,N (i, i+4) 4.2 - - - - -
dNN 2.8 2.6 4.3 4.2 2.6

2.4

4.5

2.4

dNN (i, i+2) 4.2 4.1 - - 3.8 4.3
dβN 2.5 - 4.1 2.9 - 4.4 3.2 - 4.5 3.7 - 4.7 2.9 - 4.4

3.6 - 4.6

3.6 - 4.6

3.6 - 4.6

dβN (i, i+3)b 5.3 - 5.7 5.0 - 5.7 - - - -
a For the turns, the first two numbers applies to the distance between residues 2 and 3, the second to that between residues 3 and 4. The range indicated for dN (i, i+3) corresponds to the distances adopted if ψ1 varied between -180 and 180o.

b The ranges given correspond to the distances adopted by a β-methine proton if χ1 is varied between -180 and 180o.



Reference

K. Wüthrich, M. Billeter and W. Braun, Polypeptide secondary structure determination by nuclear magnetic
resonance observation of short proton-proton distances,J. Mol. Biol. 180 (1984), pp. 715-740.