TY - JOUR
T1 - A Resonance Raman Study of the C=C Stretch Modes in Bovine and Octopus Visual Pigments with Isotopically Labeled Retinal Chromophores
AU - Huang, L.
AU - Deng, H.
AU - Koutalos, Y.
AU - Ebrey, T.
AU - Groesbeek, M.
AU - Lugtenburg, J.
AU - Tsuda, M.
AU - Callender, R. H.
PY - 1997/12
Y1 - 1997/12
N2 - Previous resonance Raman spectroscopic studies of bovine and octopus rhodopsin and bathorhodopsin in the C-C stretch fingerprint region have shown drastically different spectral patterns, which suggest different chromophore-protein interactions. We have extended our resonance Raman studies of bovine and octopus pigments to the C=C stretch region in order to reveal a more detailed picture about the difference in retinal-protein interactions between these two pigments. The C=C stretch motions of the protonated retinal Schiff base are strongly coupled to form highly delocalized ethylenic modes located in the 1500 to 1650 cm-1 spectral region. In order to decouple these vibrations, a series of 11,12-D2-labeled retinals, with additional 13C labeling at C8, C10, C11 and C14, respectively, are used to determine the difference of specific C=C stretch modes between bovine and octopus pigments. Our results show that the C9=C10 and C13=C14 stretch mode are about 20 cm-1 lower in the Raman spectrum of octopus bathorhodopsin than in bovine bathorhodopsin, while the other C=C stretch modes in these two bathorhodopsins are similar. In contrast, only the C9=C10 stretch mode in octopus rhodopsin is about 10 cm-1 lower than in bovine rhodopsin, while other C=C stretches are similar.
AB - Previous resonance Raman spectroscopic studies of bovine and octopus rhodopsin and bathorhodopsin in the C-C stretch fingerprint region have shown drastically different spectral patterns, which suggest different chromophore-protein interactions. We have extended our resonance Raman studies of bovine and octopus pigments to the C=C stretch region in order to reveal a more detailed picture about the difference in retinal-protein interactions between these two pigments. The C=C stretch motions of the protonated retinal Schiff base are strongly coupled to form highly delocalized ethylenic modes located in the 1500 to 1650 cm-1 spectral region. In order to decouple these vibrations, a series of 11,12-D2-labeled retinals, with additional 13C labeling at C8, C10, C11 and C14, respectively, are used to determine the difference of specific C=C stretch modes between bovine and octopus pigments. Our results show that the C9=C10 and C13=C14 stretch mode are about 20 cm-1 lower in the Raman spectrum of octopus bathorhodopsin than in bovine bathorhodopsin, while the other C=C stretch modes in these two bathorhodopsins are similar. In contrast, only the C9=C10 stretch mode in octopus rhodopsin is about 10 cm-1 lower than in bovine rhodopsin, while other C=C stretches are similar.
UR - http://www.scopus.com/inward/record.url?scp=0031301653&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0031301653&partnerID=8YFLogxK
U2 - 10.1111/j.1751-1097.1997.tb03219.x
DO - 10.1111/j.1751-1097.1997.tb03219.x
M3 - Article
C2 - 9421961
AN - SCOPUS:0031301653
SN - 0031-8655
VL - 66
SP - 747
EP - 754
JO - Photochemistry and Photobiology
JF - Photochemistry and Photobiology
IS - 6
ER -