Am. Rodriguez et al., A CYTOCHROME P450-LIKE GENE POSSIBLY INVOLVED IN OLEANDOMYCIN BIOSYNTHESIS BY STREPTOMYCES-ANTIBIOTICUS, FEMS microbiology letters, 127(1-2), 1995, pp. 117-120
A cosmid clone from an oleandomycin producer, Streptomyces antibioticu
s, contains a large open reading frame encoding a type I polyketide sy
nthase subunit and an oleandomycin resistance gene (oleB). Sequencing
of a 1.4-kb DNA fragment adjacent to oleB revealed the existence of an
open reading frame (oleP) encoding a protein similar to several cytoc
hrome P450 monooxygenases from different sources, including the produc
ts of the eryF and elyK genes from Saccharopolyspora erythraea that pa
rticipate in erythromycin biosynthesis. The oleP gene was expressed in
Escherichia coli as a fusion protein to a maltose-binding protein. Us
ing polyclonal antibodies against this fusion protein it was observed
that the synthesis of the cytochrome P450 was in parallel to that of o
leandomycin. The cytochrome P450 encoded by the oleP gene could be res
ponsible for the epoxidation of carbon 8 of the oleandomycin lactone r
ing.