Fig. 1.

Submitochondrial localization of GLDH. Purified mitochondria (tot) were fractionated and the following submitochondrial compartments were isolated: matrix (ma), inner membrane (IM), intermembrane space (IMS) and outer membrane (OM). Integral proteins of IM (IMi) and peripheral proteins of IM (IMp) were separated by performing an alkali treatment of the IM (see “Material and methods”). In addition, mitochondria were swollen to obtain mitoplasts (swollen mitochondria lacking the outer membrane). Mitoplasts (mt−) were treated with proteinase K to digest the protein domains of the IM facing the IMS (mt+). The different fractions were separated by SDS-PAGE and western blots using anti-GLDH antibodies and antibodies against marker proteins for each compartment were performed