Generation of Novel Landomycins M and O through Targeted Gene Disruption

Abstract Two genes from Streptomyces cyanogenous S136 that encode the reductase LanZ4 and the hydroxylase LanZ5, which are involved in landomycin A biosynthesis, were characterized by targeted gene inactivation. Analyses of the corresponding mutants as well as complementation experiments have allowed us to show that LanZ4 and LanZ5 are responsible for the unique C‐11‐hydroxylation that occurs during landomycin biosynthesis. Compounds accumulated by the lanZ4/Z5 mutants are the previously described landomycin F and the new landomycins M and O.