Membrane extraction of Pex17HAp. Organelle membranes from oleate-grown cells expressing Pex17HAp (SWS17HA) were extracted with the indicated buffers and repelleted. The supernatant (s) and pellet (p) fractions were analyzed by immunoblotting with the indicated antibodies. carbonate, 0.1 M sodium carbonate, pH 11; Tris, 10 mM Tris-HCl, pH 8.0; buffer, original lysis buffer only; 1% Triton X-100, original lysis buffer with 1% Triton X-100.