Depolarized Light Scattering Intensity Temperatur; Anomalies in Thin Oriented Purple Membrane Film

Abstract The depolarized light scattering intensity (IS) temperature dependence was investigated in suspension of purple membranes from Halobacterium hallobium, sandwiched as a thin oriented film by the glass plate walls. Three anomalies of IS =f(T) were registered at (33-37)°C, (66-71)°C and (92-95)°C. The third anomaly was connected with irreversible changes in bacteriorhodopsin state, probably due to its denaturation. The other anomalies were connected with changes in orientation, mobility and structure of membrane lipids and the bacteriorhodopsin, i.e. they appear like smeared second order phase transitions with partial bacteriorhodopsin denaturation.