Table 1.

Comparison of canthaxanthin dihedral angles observed in OCP structures in the three states: Dark, I1 and I4. Dihedral angles were measured using atomic PDB coordinates for carbon atoms

	Dark (this study)	1 m (this study)	10 m (this study)	Syn OCPCAN (4XB5)	Syn OCPECH (5TUX)	Arth OCPhECH (5UI2 -CA)	Arth OCPhECH (5UI2 -CB)
C5-C6-C7-C8 (β1 ring)	153	157.8	−35.6	116.3	131.8	118.5	131.9
C6-C7-C8-C9	160	163.1	159.9	175.4	176.7	172.8	174.7
C7-C8-C9-C10	167	160.4	167	−155.3	−168.7	−163.7	−176.8
C8-C9-C10-C11	164.9	162.4	164.9	175.8	174.9	177.9	171.1
C9-C10-C11-C12	−176.1	−166.1	−176.2	178.8	−179.5	165.2	173.6
C10-C11-C12-C13	176.9	−172.8	177.0	174.4	173.7	175.4	175.5
C11-C12-C13-C14	177.6	163	177.7	167.8	170	177.5	175.9
C12-C13-C14-C15	172.7	175.4	172.7	173	172.8	171	170
C13-C14-C15-C15’	175	−176.2	175	−171.4	177.8	−175.7	171.5
C14-C15-C15’-C14’	172.4	144.9	172.4	172.7	171.8	170.7	171.4
C15-C15’-C14’-C13’	−175.2	163.8	−175.2	169.8	−178.7	179.6	−168.2
C15’-C14’-C13’-C12’	171.5	−177.5	171.5	173	172.2	172.8	169.8
C14’-C13’-C12’-C11’	−170.9	−148.1	−170.9	−153.3	−165.9	−161.6	171.4
C13’-C12’-C11’-C10’	172	171	172	173.1	172.8	174.8	170.9
C12’-C11’-C10’-C9’	−175.9	167.5	−175.9	171.9	−179.2	170.3	−158.8
C11’-C10’-C9’-C8’	172.9	173.3	172.8	175.2	174.8	174	−179.7
C10’-C9’-C8’-C7’	178.4	−23	178.3	−160.3	−175.1	−170.2	174.9
C9’-C8’-C7’-C6’	176.3	−171.6	176.3	177.6	178.5	177.3	178.6
C8’-C7’-C6’-C5’ (β2 ring)	−45.3	145.1	−45.3	−72.1	−58.6	−66	−51.9
RMSD	0.436	0.706	0.436

Dihedral angles undergoing substantial change upon illumination are highlighted in bold.

RMSD was calculated with Pymol Align using PDB entry 4XB5 as a target selection.

Deposited dihedral angles for CAN-binding (PDB entry 4XB5), ECN-binding (5TUX), and 3′-hECN-binding (5UI2) OCPs are also included for comparison.