1.14.13.38 pharmacology synthesis of chlortetracycline 438864 1.14.13.38 synthesis biosynthesis of tetracycline from anhydrotetracycline in Saccharomyces cerevisiae heterologously expressing the anhydrotetracycline hydroxylase OxyS, the dehydrotetracycline reductase CtcM, and the F420 reductase FNO from three bacterial hosts. This biosynthesis of tetracycline is enabled by OxyS performing just one hydroxylation step in S. cerevisiae -, 763803