As a result, we confirmed highly accurate conformational parameters characteristic to the "most acceptable alpha(R)-helix PLA" as follows; intrinsic dihedral angles (phi,psi,omega) = (-62 degrees, -43 degrees, 178 degrees); hydrogen-bond distances R-O center dot center dot center dot H = ...
The alpha-helix defined in 1951 by Pauling et al. on the basis of model building and X-ray fibre diffraction data has 3.65 residues per turn (n) achieved with planar peptides, torsion angles of phi = -48 degrees and psi = -57 degrees and... T Blundell,D Barlow,N Borkakoti,... ...
We find that the amide I band is inhomogeneously broadened due to conformational disorder of the helix. The 2D line shapes can be well described using distributions of the dihedral angles (#PHI##PSI#) around their average values with a width of 20 deg, confirming previous molecular-dynamics ...
Favored and allowed phi,psi regions are also defined for Pro, pre-Pro, and Gly (important because Gly phi,psi angles are more permissive but less accurately determined). Details of these accurate empirical distributions are poorly predicted by previous theoretical calculations, including a region ...
The tripeptide exists as a zwitterion in the crystal and assumes a near alpha-helical backbone conformation with the following torsion angles: psi 1 = -147.8 degrees; phi 2, psi 2 = -71.2 degrees, 33.4 degrees; phi 3, psi 3 = -78.3 degrees, -43.3 degrees. In this structure, one ...
The alpha-helix defined in 1951 by Pauling et al. on the basis of model building and X-ray fibre diffraction data has 3.65 residues per turn (n) achieved with planar peptides, torsion angles of phi = -48 degrees and psi = -57 degrees and... T Blundell,D Barlow,N Borkakoti,... ...
All four L-(alpha Me)Val residues prefer phi, psi angles in the right-handed helical region of the conformational map. The results indicate that: (i) the (alpha Me)Val residue is a strong type-I/III beta-turn and helix former, and (ii) the relationship between (alpha Me)Val ...
Guddat, L. W., J. A. Martin, L. Shan, A. B. Edmundson, and W. R. Gray. 1996. Three-dimensional structure of a-conotoxin GI at 1.2 A resolu- tion. Biochemistry. 35:11329-11335.Guddat, L.W., Martin, J.A., Shan, L., Edmundson, A.B. & Gray, W.R. (1996). Three-...
Structure validation by C alpha geometry: phi,psi and C beta deviation. Proteins: Struct. Funct. Genet. 50, 437-450.S C Lovell, I W Davis, W B Adrendall, P I W de Bakker, J M Word, M G Prisant, J S Richardson, and D C Richardson. Structure validation by C alpha geometry: ...
At least 15 classes of alpha-turns have been enumerated based on the location in the phi,psi space of the three central residues (i+1 to i+3)-one of the major being the class AAA, where the residues occupy the conventional helical backbone torsion angles. However, moving towards the C-...