FIG. 4.

Detergent extracts of Δleu5 mitochondria contain wild-type levels of α-IPMS activity. Mitochondria were isolated from wild-type and Δleu5 cells grown in YPGal medium. They were lysed in SoH buffer containing 0.05% Triton X-100 and centrifuged for 10 min at 12,000 × g. The clarified extract was incubated for 0 or 15 min with 2 mM α-ketoisovalerate (KIV) and 1 mM acetyl-CoA as indicated. α-IPM was determined as described for Fig. 3B. a.u., arbitrary units.