A method to obtain right-side-out and sealed plasma membrane vesicles from the filamentous fungus Penicillium simplicissimum

Plasma membrane vesicles were purified from the citrate excreting filamentous fungus Penicillium simplicissimum. The hyphae were disrupted by grinding in a glass bead mill and plasma membranes were obtained from a crude membrane fraction by partitioning in an aqueous dextran/polyethylene glycol two-phase system. The resulting enriched plasma membrane fraction contained only minor contaminations of marker enzymes of intracellular membranes, consisted of more than 90% of right-side-out vesicles and was sealed for potassium.