| Abstract: | Fluidity of the plasma membrane of Trypanosoma brucei brucei has been examined with fluorescence and electron spin resonance spectroscopy. Fluorescent probes 1,6-diphenyl-1,3,5-hexatriene and 8-anilino-1-naphthalene sulfonate and the spin label probe 5-doxyl stearate have been employed to examine fluidity under a variety of conditions. The temperature dependence of 8-anilino-1-naphthalene sulfonate polarization and of the order parameter S for 5-doxyl stearate reveals phase alterations near 30 C. 1,6-Diphenyl-1,3,5-hexatriene polarization shows that proteolysis of the surface glycoprotein with trypsin increases fluidity but treatment with human serum which is trypanocidal produces no detectable change in membrane fluidity. |
