Dissection of Factors Affecting the Variability of the Peptide Bond Geometry and Planarity

Table 3

Average values of bond angles with standard deviations and occurrences (in bracket) of non-Gly/non-Pro residues in β-structure or coil in the 15°  × 15° box centered at = (−120°, 130°). The differences (coil minus β-sheet) between the average values of the distributions and the statistical significance of these differences ( value) are reported.

Bond angle			Difference	value
	β-Sheet; (14076)	Coil; (1968)
NC^αC	108.8 ± 1.9	109.0 ± 2.2	0.2
C^αCO	120.4 ± 0.9	120.4 ± 0.9	0.0	0.58
C^αCN^+1	116.4 ± 1.1	116.6 ± 1.1	0.2
OCN^+1	123.2 ± 0.9	123.0 ± 1.0	−0.2
C^−1NC^α	122.5 ± 1.3	122.6 ± 1.4	0.1	0.15
NC^αC^β	110.9 ± 1.4	110.7 ± 1.4	−0.2
C^βC^αC	109.7 ± 1.5	109.7 ± 1.6	0.0	0.27