FIGURE 1.

Comparison of reactions catalyzed and organization of acyl-CoA mutases. A, reactions catalyzed by acyl-CoA mutases. IcmF can also catalyze the PCM reaction, albeit inefficiently. B, organization of ICM and PCM variants. ICM and PCM are heterotetramers in which two small B₁₂-binding subunits interact with two large substrate-binding subunits. IcmF is a natural variant in which the small and large subunits found in ICM are fused via a middle G-protein chaperone domain. PCM-F is an artificially engineered variant of PCM (this study) in which the large and small subunits have been fused via an 11-amino acid linker as described under “Experimental Procedures.”