Propionyl-CoA carboxylase (PCC) is a biotin-dependent mitochondrial enzyme that catalyzes the conversion of propionyl-CoA to D-methylmalonyl-CoA. PCC consists of two heterologous subunits, alpha PCC and beta PCC, which are encoded by the nuclear PCCA and PCCB genes, respectively. Deficiency of PCC results in a metabolic disorder, propionic acidemia, which is sufficiently severe to cause neonata...