Biomaterial Database

Specific photoisomerization of retinal in squid rhodopsin and metarhodopsin. 1981

T Suzuki, and M Makino

The composition of retinal isomers in the photosteady-state mixtures formed from squid rhodopsin and metarhodopsin was determined by high-pressure liquid chromatography. A large amount of 9-cis-retinal was obtained at liquid N2 temperature when rhodopsin was irradiated with orange light, but only small quantities of 9-cis-retinal were obtained at 15 degrees C. Scarcely any 9-cis-retinal was produced from metarhodopsin by irradiation at liquid N2 temperature. A large quantity of 7-cis-retinal was found in the photoproduct of rhodopsin irradiated at solid carbon dioxide temperature, but not at 15 degrees C and liquid N2 temperature. 7-cis-Retinal was not produced from metarhodopsin at any temperatures. These results indicate that the photoisomerization of retinal is regulated by the structure of the retinal-binding site of this protein. The formation of 9-cis- and 7-cis-retinals is forbidden in the metarhodopsin protein.

UI	MeSH Term	Description	Entries
D008027	Light	That portion of the electromagnetic spectrum in the visible, ultraviolet, and infrared range.	Light, Visible,Photoradiation,Radiation, Visible,Visible Radiation,Photoradiations,Radiations, Visible,Visible Light,Visible Radiations
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012168	Retinal Pigments	Photosensitive protein complexes of varied light absorption properties which are expressed in the PHOTORECEPTOR CELLS. They are OPSINS conjugated with VITAMIN A-based chromophores. Chromophores capture photons of light, leading to the activation of opsins and a biochemical cascade that ultimately excites the photoreceptor cells.	Retinal Photoreceptor Pigment,Retinal Pigment,Visual Pigment,Visual Pigments,Retinal Photoreceptor Pigments,Photoreceptor Pigment, Retinal,Photoreceptor Pigments, Retinal,Pigment, Retinal,Pigment, Retinal Photoreceptor,Pigment, Visual,Pigments, Retinal,Pigments, Retinal Photoreceptor,Pigments, Visual
D012172	Retinaldehyde	A diterpene derived from the carotenoid VITAMIN A which functions as the active component of the visual cycle. It is the prosthetic group of RHODOPSIN (i.e., covalently bonded to ROD OPSIN as 11-cis-retinal). When stimulated by visible light, rhodopsin transforms this cis-isomer of retinal to the trans-isomer (11-trans-retinal). This transformation straightens-out the bend of the retinal molecule and causes a change in the shape of rhodopsin triggering the visual process. A series of energy-requiring enzyme-catalyzed reactions convert the 11-trans-retinal back to the cis-isomer.	11-trans-Retinal,3,7-dimethyl-9-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4,6,8-Nonatetraenal,Axerophthal,Retinal,Retinene,Retinyl Aldehydde,Vitamin A Aldehyde,all-trans-Retinal,11-cis-Retinal,11 cis Retinal,11 trans Retinal,Aldehydde, Retinyl,Aldehyde, Vitamin A,all trans Retinal
D012243	Rhodopsin	A purplish-red, light-sensitive pigment found in RETINAL ROD CELLS of most vertebrates. It is a complex consisting of a molecule of ROD OPSIN and a molecule of 11-cis retinal (RETINALDEHYDE). Rhodopsin exhibits peak absorption wavelength at about 500 nm.	Visual Purple
D013057	Spectrum Analysis	The measurement of the amplitude of the components of a complex waveform throughout the frequency range of the waveform. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Spectroscopy,Analysis, Spectrum,Spectrometry
D013237	Stereoisomerism	The phenomenon whereby compounds whose molecules have the same number and kind of atoms and the same atomic arrangement, but differ in their spatial relationships. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 5th ed)	Molecular Stereochemistry,Stereoisomers,Stereochemistry, Molecular,Stereoisomer
D013696	Temperature	The property of objects that determines the direction of heat flow when they are placed in direct thermal contact. The temperature is the energy of microscopic motions (vibrational and translational) of the particles of atoms.	Temperatures
D014801	Vitamin A	Retinol and derivatives of retinol that play an essential role in metabolic functioning of the retina, the growth of and differentiation of epithelial tissue, the growth of bone, reproduction, and the immune response. Dietary vitamin A is derived from a variety of CAROTENOIDS found in plants. It is enriched in the liver, egg yolks, and the fat component of dairy products.	Retinol,11-cis-Retinol,3,7-dimethyl-9-(2,6,6-trimethyl-1-cyclohexen-1-yl)-2,4,6,8-nonatetraen-1-ol, (all-E)-Isomer,All-Trans-Retinol,Aquasol A,Vitamin A1,All Trans Retinol