HelixConstraint F12 Q19 0.795 HelixConstraint T36 A45 0.618 HelixConstraint V73 M77 0.81 HelixConstraint L85 A93 0.778 HelixConstraint L107 L111 0.67 StrandConstraint W161 G162 0.63 StrandConstraint T164 V165 0.645 StrandConstraint L176 Y179 0.632