HelixConstraint K3 A6 0.625 StrandConstraint Y19 P22 0.616 HelixConstraint L36 K42 0.803 HelixConstraint A48 M51 0.667 StrandConstraint E57 L59 0.607 HelixConstraint E61 Y62 0.621 HelixConstraint D64 Q74 0.617