SPECTRAL PROPERTIES OF BACTERIORHODOPSIN ANALOG OBTAINED BY RECONSTITUTION OF BACTERIOOPSIN WITH 4-KETO-RETINAL INVIVO

The spectral comparative investigation of protein-chromophore interact ion and of photochemical activity in bacteriorhodopsin analogs contain ing 4-keto-retinal was performed. The analogs were obtained either by hydroxylaminolysis of the purple membranes from wild type halobacteria followed by reconstitution with 4-keto-retinal or by in vivo reconsti tution of the membranes of mutant retinal-lacking strain with 4-keto-r etinal. The differences revealed in CD spectra and in pH-dependence of photocycle kinetics can be ascribed to the different structure of the protein in membranes of mutant and wild type.