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PubMed · 8117259

Rhodopsin's secondary structure revisited: assignment of structural elements.

A M Pistorius·W J de Grip
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Abstract

FT-IR spectroscopy has been applied to study the secondary structure of rhodopsin in dehydrated films of bovine rod photoreceptor membranes. Curve fitting analysis of the amide I band around 1658 cm-1 compares well with data obtained from samples in the hydrated state. Repeating this analysis on samples, treated with proteinase K or thermolysin, secondary structural elements at the cytoplasmic side of the photoreceptor membrane can be located. We present evidence for the location of a beta-sheet and a beta-turn near the lipid anchor in the C-terminal region of the protein, and for an alpha-helical structure in the third cytoplasmic loop.

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Endopeptidase KProtein Structure, SecondaryRhodopsinRod Cell Outer SegmentSerine EndopeptidasesSpectroscopy, Fourier Transform InfraredThermolysinJournal ArticleResearch Support, Non-U.S. Gov't

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A M Pistorius, W J de Grip. 1994-02-15. Rhodopsin's secondary structure revisited: assignment of structural elements.. https://doi.org/10.1006/bbrc.1994.1148

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