1. Biosynthesis of erythromycin A
Biosynthesis of erythromycin A. (A) The nucleotide sequence of the eryA region contains three ORFs designatederyAI, eryAII, and eryAIII (29,60).
Biosynthesis of erythromycin A. (A) The nucleotide sequence of the eryA region contains three ORFs designatederyAI, eryAII, and eryAIII (29,60). (B) These genes encode three proteins which constitute erythromycin B synthetase (DEBS); these are designated DEBS 1, DEBS 2, and DEBS 3 (39). (C) Each DEBS protein contains two modules, each with domains for acetyltransferase (AT), ACP, and β-keto synthase (KS) activity. Some modules contain additional domains for dehydratase (DH), enoyl reductase (ER), ketoreductase (KR), and TE activity. (D) Cyclization and release of the DEBS 3 product results in the formation of 6-deoxyerythronolide B (DEB), and additional tailoring steps result in the production of erythromycin A (E). Modified from reference 99.
Carol L. Bender et al. Microbiol. Mol. Biol. Rev. 1999; doi: