We have determined the genome sequences of 8.7 Mb chromosome of Streptomyces peucetiusATCC 27952, which produces clinically important anthracyline chemotherapeutic agents of the polyketide class of antibiotics, daunorubicin and doxorubicin. The cytochrome P450 gene superfamily is represented by 19 sequences in the S. peucetius. Amongthose, 15 code for apparently functional genes whereas four are apparently pseudo genes. Four cytochrome P450s are associated with modular PKS of avermectin, and two with doxorubicin biosynthetic gene cluster. CYP252A1 is the new family found in S. peucetius, which shares 38% identity to CYP51 from Streptomyces coelicolor A3 (2).