Figure 2.

In-gel activity staining reveals isolated complex I deficiency. Heart (A), skeletal muscle (B), liver (C), and fibroblasts (D) of patient and of a control sample were homogenized, and solubilized respiratory chain enzyme complexes from a mitochondrial membrane pellet were separated on a non-denaturing blue native polyacrylamide gel and the activity assessed with in gel activity stains. In comparison to control samples, the patient had decreased complex I activity in muscle, heart, and liver, whereas activity appeared normal in fibroblasts. The activities of complexes II, IV and V were normal.