Figure 4.

Proposed organization of, and pathway mediated by, the aminoacetone utilization microcompartment. Aminoacetone is imported into the cell via a aminopropanol permease (AAP). It is then reduced to (S)-aminopropanol by APDH, which is in turn phosphorylated APK. Both of these reactions occur in the cytosol. Aminopropanol-phosphate then enters the microcompartment through the shell, and is transformed into propionaldehyde by (S)-1-amino-2-propanol-phosphate phospho-lyase (APPL). Propionaldehyde escapes through the shell, and is captured by propionaldehyde dehydrogenase (AldDH), which adheres to the exterior face of the microcompartment via its encapsulation peptide.