Studies with retinal pigments: modified point charge model for bacteriorhodopsin and difference
نویسندگان
چکیده
Incorporation of dihydroretinals into the sensory rhodopsin SR and bacteriorhodopsin bR has led to a modified version of the external point-charge model for bR proposed in 1979. Difference Fourier transform infrared studies of native bR and bR analogs cultured on media containing isotopes of amino acids have shown some of the amino acids which undergo environmental changes or deprotonation/protonation during the bR photocycle leading to proton translocation. The proton pumping abilities of some bR analogs are compared. A visual pigment analog containing a nine-membered retinal has been prepared and studies such as FTIR are under study.
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