Title | Glycosylation of acyl carrier protein-bound polyketides during pactamycin biosynthesis. |
Publication Type | Journal Article |
Year of Publication | 2019 |
Authors | Eida AA, Abugrain ME, Brumsted CJ, Mahmud T |
Journal | Nat Chem Biol |
Volume | 15 |
Issue | 8 |
Pagination | 795-802 |
Date Published | 2019 08 |
ISSN | 1552-4469 |
Keywords | Bacterial Proteins, Carrier Proteins, Cloning, Molecular, Gene Expression Regulation, Bacterial, Pactamycin, Polyketide Synthases, Polyketides, Protein Binding, Streptomyces |
Abstract | Glycosylation is a common modification reaction in natural product biosynthesis and has been known to be a post-assembly line tailoring process in glycosylated polyketide biosynthesis. Here, we show that in pactamycin biosynthesis, glycosylation can take place on an acyl carrier protein (ACP)-bound polyketide intermediate. Using in vivo gene inactivation, chemical complementation and in vitro pathway reconstitution, we demonstrate that the 3-aminoacetophenone moiety of pactamycin is derived from 3-aminobenzoic acid by a set of discrete polyketide synthase proteins via a 3-(3-aminophenyl)3-oxopropionyl-ACP intermediate. This ACP-bound intermediate is then glycosylated by an N-glycosyltransferase, PtmJ, providing a sugar precursor for the formation of the aminocyclopentitol core structure of pactamycin. This is the first example of glycosylation of a small molecule while tethered to a carrier protein. Additionally, we demonstrate that PtmO is a hydrolase that is responsible for the release of the ACP-bound product to a free β-ketoacid that subsequently undergoes decarboxylation. |
DOI | 10.1038/s41589-019-0314-6 |
Alternate Journal | Nat Chem Biol |
PubMed ID | 31308531 |
PubMed Central ID | PMC6642016 |
Grant List | R01 AI129957 / AI / NIAID NIH HHS / United States R15 GM112068 / GM / NIGMS NIH HHS / United States |