Pellet was
dried at RT, then suspended in 2.5 ml of 50 mM Trizma-Base (Sigma-
Aldrich) buffer, pH 8.0 with 0.05% (w/v) Zwittergent Z 3-14® and
10 mM EDTA (Sigma-Aldrich), stirred for 1 h at RT and subsequently
kept at 4 °C overnight. Insoluble material was removed from OMPs
solution by centrifugation (8700 rpm, 4 °C, 10 min).