Redox activity ofHydrodictyon reticulatum plasmalemma vesicles

Plasmalemma vesicles with preserved redox activity were prepared from nets ofHydrodictyon reticulatum. Since the walls are mechanically very resistant, a combination of partial cell-wall enzyme digestion and ultrasonic homogenization had to be used for the disruption of cells. To isolate the plasma-membrane-enriched microsomal fraction separation in an aqueous two-phase polymer system was found to be most suitable. The right-side-out vesicles reduced added hexacyanoferrate(III) by electrons supplied either by a transmembrane flow or from external NADH.