Coexistence of Domains with Distinct Order and Polarity in Fluid Bacterial Membranes¶ Academic Article uri icon


  • In this study we sought the detection and characterization of bacterial membrane domains. Fluorescence generalized polarization (GP) spectra of laurdan-labeled Escherichia coli and temperature dependencies of both laurdan's GP and fluorescence anisotropy of 1, 3- diphenyl-1, 3, 5-hexatriene (DPH)(rDPH) affirmed that at physiological temperatures, the E. coli membrane is in a liquid-crystalline phase. However, the strong excitation wavelength dependence of rlaurdan at 37° C reflects membrane heterogeneity. Time-resolved fluorescence emission spectra, which display distinct biphasic redshift kinetics, verified the coexistence of two subpopulations of laurdan. In the initial phase,< 50 ps, the redshift in the spectral mass center is much faster for laurdan excited at the blue edge (350 nm), whereas at longer time intervals, similar kinetics is observed upon excitation at either blue or red …

publication date

  • July 1, 2002