Sandbox Reserved 819: Difference between revisions

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Retinal is a polyene chromophore and allows to convert light into metabolic energy. It absorbs visible light maximally at 550-570 nm.

It catches a photon, leading to a conformational change of the rhodopsin. This is an isomerization of the 11-cis-retinal into a ll-trans-retinal. Retinal binds covalently to the lysine 221 on the transmembrane helix nearest the C-terminus of the protein through a Schiff base linkage. Formation of the Schiff base linkage involves removing the oxygen atom from retinal and two hydrogen atoms from the free amino group of lysine, giving H2O. Retinylidene is the divalent group formed by removing the oxygen atom from retinal, and so opsins is called retinylidene proteins. A Schiff base is a compound with a functional group made up of a carbon-nitrogen double bond with a nitrogen atom connected to an aryl or alkyl group, not hydrogen. Schiff bases in a broad sense have the general formula R1-R2-C=N-R3, where R is an organic side chain. In this definition, Schiff base is synonymous with azomethine. The chain on the nitrogen makes the Schiff base a stable imine. A Schiff base derived from an aniline, where R3 is a phenyl or a substituted phenyl.~~<ref>{{GoldBookRef | title = Schiff base | file = S05498}}</ref>~~

It catches a photon, leading to a conformational change of the rhodopsin. This is an isomerization of the 11-cis-retinal into a ll-trans-retinal. Retinal binds covalently to the lysine 221 on the transmembrane helix nearest the C-terminus of the protein through a Schiff base linkage. Formation of the Schiff base linkage involves removing the oxygen atom from retinal and two hydrogen atoms from the free amino group of lysine, giving H2O. Retinylidene is the divalent group formed by removing the oxygen atom from retinal, and so opsins is called retinylidene proteins. A Schiff base is a compound with a functional group made up of a carbon-nitrogen double bond with a nitrogen atom connected to an aryl or alkyl group, not hydrogen. Schiff bases in a broad sense have the general formula R1-R2-C=N-R3, where R is an organic side chain. In this definition, Schiff base is synonymous with azomethine. The chain on the nitrogen makes the Schiff base a stable imine. A Schiff base derived from an aniline, where R3 is a phenyl or a substituted phenyl.

Sandbox Reserved 819: Difference between revisions

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Revision as of 16:13, 4 January 2014 view source Allan Bernard (talk \| contribs) 142 edits No edit summary ← Older edit		Revision as of 16:14, 4 January 2014 view source Allan Bernard (talk \| contribs) 142 edits No edit summary Newer edit →
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	Retinal is a polyene chromophore and allows to convert light into metabolic energy. It absorbs visible light maximally at 550-570 nm.		Retinal is a polyene chromophore and allows to convert light into metabolic energy. It absorbs visible light maximally at 550-570 nm.
	It catches a photon, leading to a conformational change of the rhodopsin. This is an isomerization of the 11-cis-retinal into a ll-trans-retinal. Retinal binds covalently to the lysine 221 on the transmembrane helix nearest the C-terminus of the protein through a Schiff base linkage. Formation of the Schiff base linkage involves removing the oxygen atom from retinal and two hydrogen atoms from the free amino group of lysine, giving H2O. Retinylidene is the divalent group formed by removing the oxygen atom from retinal, and so opsins is called retinylidene proteins. A Schiff base is a compound with a functional group made up of a carbon-nitrogen double bond with a nitrogen atom connected to an aryl or alkyl group, not hydrogen. Schiff bases in a broad sense have the general formula R1-R2-C=N-R3, where R is an organic side chain. In this definition, Schiff base is synonymous with azomethine. The chain on the nitrogen makes the Schiff base a stable imine. A Schiff base derived from an aniline, where R3 is a phenyl or a substituted phenyl.~~<ref>{{GoldBookRef \| title = Schiff base \| file = S05498}}</ref>~~		It catches a photon, leading to a conformational change of the rhodopsin. This is an isomerization of the 11-cis-retinal into a ll-trans-retinal. Retinal binds covalently to the lysine 221 on the transmembrane helix nearest the C-terminus of the protein through a Schiff base linkage. Formation of the Schiff base linkage involves removing the oxygen atom from retinal and two hydrogen atoms from the free amino group of lysine, giving H2O. Retinylidene is the divalent group formed by removing the oxygen atom from retinal, and so opsins is called retinylidene proteins. A Schiff base is a compound with a functional group made up of a carbon-nitrogen double bond with a nitrogen atom connected to an aryl or alkyl group, not hydrogen. Schiff bases in a broad sense have the general formula R1-R2-C=N-R3, where R is an organic side chain. In this definition, Schiff base is synonymous with azomethine. The chain on the nitrogen makes the Schiff base a stable imine. A Schiff base derived from an aniline, where R3 is a phenyl or a substituted phenyl.