Rhodopsin's secondary structure revisited: assignment of structural elements.
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.
Pistorius
A M
AM
Department of Biochemistry, University of Nijmegen, The Netherlands.
de Grip
W J
WJ
D019286:Endopeptidase K; D017433:Protein Structure, Secondary; D012243:Rhodopsin / Q000737:chemistry* / Q000302:isolation & purification; D012374:Rod Cell Outer Segment / Q000378:metabolism; D012697:Serine Endopeptidases; D017550:Spectroscopy, Fourier Transform Infrared; D013820:Thermolysin
D012243:Rhodopsin; D012697:Serine Endopeptidases; D019286:Endopeptidase K; D013820:Thermolysin