The enzyme is responsible for the C-12 hydroxylation of the macrolactone ring, one of the last steps in erythromycin biosynthesis. It shows 1200-1900-fold preference for erythromycin D over the alternative substrate erythromycin B .
in a Saccharopolyspora venezuelae pikC deletion mutant, EryK can catalyze the hydroxylation of YC-17 and narbomycin to generate methymycin/neomethymycin and pikromycin, respectively. EryK is flexible toward some alternative polyketides and can be useful for structural diversification of macrolides by post-polyketide synthase hydroxylation
different crystal forms are harvested from distinct crystallization conditions: two ligand-free forms, one substrate bound and two inhibitors-bound. All crystals belong either to the monoclinc P2(1)or to the orthorhombic P2(1)2(1)2(1) space groups, and exhibit diffraction limits ranging from 2.3 to 1.6 A
vapor diffusion at 21°C, three crystal forms of EryK are obtained in different crystallization conditions: with His tag (His6-EryK) in low salt conditions, without tag (EryK) in high salt, and in complex with its substrate erythromycin D (ErD-EryK)
systematically modulating the enzyme amounts of EryK and EryG by integrating additional eryK and eryG copies into the industrial strain Saccharopolyspora erythraea HL3168 E3 significantly enhances the process of biotransformation from erythromycin-D to erythromycin-A, nearly completely eliminates the by-products erythromycin-B and erythromycin-C, and efficiently improves erythromycin-A production and purity at the fermentation stage. In conjunction with other traditional and genetic ways to continuously evaluate the erythromycin-A production system