Involved in the biosynthesis of the anthracyclines carminomycin, daunorubicin (daunomycin) and doxorubicin (adriamycin) which are aromatic polyketide antibiotics that exhibit high cytotoxicity and are widely applied in the chemotherapy of a variety of cancers. In vivo, DoxA catalyzes the C-13 hydroxylation of 13-deoxycarminomycin and 13-deoxydaunorubicin to yield 13-dihydrocarminomycin and 13-dihydrodaunorubicin, respectively, as well as the oxidation of these 13-dihydro-anthracyclines to their respective 13-keto forms, carminomycin and daunorubicin. In vivo, it also catalyzes the C-14 hydroxylation of daunorubicin to form doxorubicin. It can only use NADP. DoxA acts jointly with DnrV. 13-deoxydaunorubicin + H(+) + NADPH + O2 = 13-dihydrodaunorubicin + H2O + NADP(+) 13-dihydrodaunorubicin + H(+) + NADPH + O2 = daunorubicin + 2 H2O + NADP(+) 13-deoxycarminomycin + H(+) + NADPH + O2 = 13-dihydrocarminomycin + H2O + NADP(+) 13-dihydrocarminomycin + H(+) + NADPH + O2 = carminomycin + 2 H2O + NADP(+) daunorubicin + H(+) + NADPH + O2 = doxorubicin + H2O + NADP(+) Antibiotic biosynthesis; daunorubicin biosynthesis. Antibiotic biosynthesis; carminomycin biosynthesis. Antibiotic biosynthesis; doxorubicin biosynthesis. Monomer. S.peucetius subsp. caesius ATCC 27952, a mutant strain derived from S.peucetius ATCC 29050, is the only organism reported to produce doxorubicin in vivo (PubMed:5365804). Belongs to the cytochrome P450 family.