Ab initio study of {sup 13}C NMR chemical shifts for the chromophores of rhodopsin and bacteriorhodopsin. 2. Comprehensive analysis of the {sup 13}C chemical shifts of protonated all-trans-retinylidene Schiff base

Journal Article · Thu Feb 01 00:00:00 EST 1996 · Journal of Physical Chemistry

DOI:https://doi.org/10.1021/jp952294u· OSTI ID:199382

Sakurai, Minoru; Wada, Mitsuhito; Inoue, Yoshio ^[1]; Tamura, Yusuke; Watanabe, Yoichi ^[2]

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1. Tokyo Inst. of Technology, Yokohama (Japan)
2. Cray Research Japan Ltd., Tokyo (Japan)

Theoretical analysis was performed for the {sup 13}C chemical shifts of the retinal chromophore in bacteriorhodopsin (bR) by means of ab initio NMR shielding calculation, based on the localized orbital/ local origin method. In order to comprehensively investigate the correlation between the {sup 13}C chemical shieldings of the unsaturated carbons and physicochemical perturbations relating to the spectral tuning of bacteriorhodopsin, the following three factors are taken into account in the present calculation: (1) change in strength of the hydrogen bonding between protonated retinylidene Schiff base and its counterion, (2) conformational changes about single bonds of the conjugated chain, and (3) electrostatic interactions between the Schiff base and electric dipoles. On the basis of these calculations, we successfully find a molecular model for which the shielding calculation almost completely reproduces the observed chemical shift data for the chromophore of bR. 47 refs., 13 figs.

• OSTI ID: 199382
• Journal Information: Journal of Physical Chemistry, Vol. 100, Issue 5; Other Information: PBD: 1 Feb 1996
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
40 CHEMISTRY
66 PHYSICS
99 MATHEMATICS
COMPUTERS
INFORMATION SCIENCE
MANAGEMENT
LAW
MISCELLANEOUS
PROTEINS
CHEMICAL SHIFT
NMR SPECTRA
SCHIFF BASES
RHODOPSIN
PHOTOSYNTHETIC BACTERIA
NUCLEAR MAGNETIC RESONANCE
CALCULATION METHODS
MOLECULAR MODELS
OPTICAL PROPERTIES