Metabolizes sarcosine, L-pipecolic acid and L-proline. H2O + O2 + sarcosine = formaldehyde + glycine + H2O2 L-pipecolate + O2 = H(+) + H2O2 + L-1-piperideine-6-carboxylate Binds 1 FAD per subunit. Monomer. Kidney and liver. Belongs to the MSOX/MTOX family.