Retinal isomerase catalyses the conversion of?
A. 11-cis retinal to rhodopsin
B. All trans retinal to 11-cis retinal
C. Lumirhodopsin to metarhodopsin
C. Bathorhodopsin to lumirhodopsin
Correct answer : B. All trans retinal to 11-cis retinal
- When light energy is absorbed by rhodopsin, photoactivation of electrons in the retinal portion of rhodopsin leads to the change of cis form of retinal into the all trans form.
- The first stage in the reformation of rhodopsin is to reconvert the all trans retinal into 11 cis retinal.
- This process is catalysed by the enzyme – retinal isomerase.
Ref: Textbook of Medical Physiology, Guyton and Hall, 11th edition, page 629.