Photopigment
Photopigments are unstable pigments that undergo a chemical change when they absorb light. The term is generally applied to the non-protein
photoreception. In medical terminology, "photopigment" commonly refers to the photoreceptor proteins of the retina.[1]
Photosynthetic pigments
thylakoid membranes of plant chloroplasts).[2] In chloroplasts, the light-driven electron transfer chain in turn drives the pumping of protons across the membrane.[2]
Photoreceptor pigments
The pigments in
photoreduction when they absorb a photon.[3] This change in the conformation or redox state of the chromophore then affects the protein conformation or activity and triggers a signal transduction cascade.[3]
Examples of photoreceptor pigments include:[4]
- retinal (in rhodopsin)
- flavin (in cryptochrome)
- bilin (in phytochrome)
Photopigments of the vertebrate retina
In medical terminology, the term photopigment is applied to
photopsins, the photoreceptor proteins in the retinal rods and cones of vertebrates that are responsible for visual perception, but also melanopsin and others.[5]
See also
References
- ^ Epstein, R.J. (2003). Human Molecular Biology: An Introduction to the Molecular Basis of Health and Disease. Cambridge University Press. p. 453.
- ^ a b c Blankenship (2014). Molecular Mechanisms of Photosynthesis (2nd ed.). John Wiley & Sons.
- ^ a b Nelson, Lehninger, Cox (2008). Lehninger Principles of Biochemistry (5th ed.). Macmillan. pp. 471–523.
{{cite book}}: CS1 maint: multiple names: authors list (link) - ^ Alberts; et al. (2014). Molecular Biology of the Cell (6th ed.). Garland Science.
- ^ Williams (2004). Photoreceptor Cell Biology and Inherited Retinal Degenerations. World Scientific. pp. 89–145.