Table 3.

Difference between C112 and C146 residues in RPE65 protein.

	Cysteine 112 (C112)	Cysteine 146 (C146)
Residue location in the 3-D structure	located in surface-exposed highly mobile loop	located in hydrophobic substrate-binding cleft
MS-coupled acyl exchange labeling identified modification	±Palmitoylation (shows NEM and 4-VP modification)	+Palmitoylation (only 4-VP modification)
Membrane binding of RPE65	significantly affect membrane binding	No role in membrane binding
Catalytic activity of RPE65	mutation abolishes activity	mutation reduces activity
Proposed source of palmitoyl moiety	DHHC38 -mediated palmitoylation using palmitoyl-CoA	Substrate mediated palmitoylation