Plays an important role in the metabolism of acetone derived from propane oxidation (PubMed:17071761). Catalyzes the oxidation of acetone to methyl acetate (PubMed:17071761, PubMed:30392152). Exhibits high catalytic efficiency towards various linear and cyclic ketones, such as butanone, 2-pentanone, 2-heptanone, 2-octanone, 2-nonanone, 2-decanone, cyclobutanone, cyclopentanone and cyclohexanone (PubMed:17071761, PubMed:30392152). Elicits the highest catalytic efficiency towards butanone and cyclobutanone (PubMed:30392152). Is highly specific for NADPH and cannot use NADH (PubMed:17071761, PubMed:30392152). acetone + H(+) + NADPH + O2 = H2O + methyl acetate + NADP(+) Binds 1 FAD per subunit. kcat is 2.0 sec(-1) with NADPH as substrate. kcat is 1.4 sec(-1) with acetone as substrate. kcat is 2.1 sec(-1) with butanone as substrate. kcat is 1.9 sec(-1) with 2-pentanone as substrate. kcat is 3.9 sec(-1) with 2-heptanone as substrate. kcat is 2.2 sec(-1) with 3-methylbutanone as substrate. kcat is 1.5 sec(-1) with 2,4-dimethyl-3-pentanone as substrate. kcat is 2.0 sec(-1) with cyclobutanone as substrate. kcat is 4.3 sec(-1) with cyclopentanone as substrate. kcat is 3.6 sec(-1) with cyclohexanone as substrate. kcat is 1.5 sec(-1) with bicyclo[3.2.0]hept-2-en-6-one as substrate. kcat is 1.0 sec(-1) with phenylacetone as substrate. Optimum pH is 8.0-8.5 (PubMed:17071761). Optimum pH is 7.0-8.0 (PubMed:30392152). Optimum temperature is 35 degrees Celsius. Homotetramer. Induced by propane, 2-propanol and acetone. Belongs to the FAD-binding monooxygenase family.