Table 1.

Helicity of selected peptides bound to λ boxB RNAa

	Peptide sequence	−[θ]222	#AA
λ N	MDAQTRRRERRAEKQAQWKAAN	25,800	16.0
11–10	––––––––––––ALRNEKFWVV	21,100	13.1
11–36	––––––––––––MERATLPQVL	20,600	12.8
12–39	––––––––––––LQRSRARHAL	24,100	14.9
12–47	––––––––––––LERTKLEKAL	21,000	13.0
12–50	––––––––––––NMRMYRSLVI	22,700	14.1

^a The first 12 amino acids are identical in all peptides. [θ]₂₂₂ is the molar ellipticity per amino acid residue in deg cm² dmol⁻¹ from the bound peptide difference spectrum. #AA is the number of helical amino acids calculated from [θ]₂₂₂. We estimate a <5% error in the measurement of [θ]₂₂₂. There may be as high as a 15% error in #AA for λ N, 11–10, and 12–50 due to aromatic side chain contributions to [θ]₂₂₂.