Title | Structure of a bound peptide phosphonate reveals the mechanism of nocardicin bifunctional thioesterase epimerase-hydrolase half-reactions. |
Publication Type | Journal Article |
Year of Publication | 2019 |
Authors | Patel KD, d'Andrea FB, Gaudelli NM, Buller AR, Townsend CA, Gulick AM |
Journal | Nat Commun |
Volume | 10 |
Issue | 1 |
Pagination | 3868 |
Date Published | 2019 Aug 27 |
ISSN | 2041-1723 |
Abstract | Nonribosomal peptide synthetases (NRPSs) underlie the biosynthesis of many natural products that have important medicinal utility. Protection of the NRPS peptide products from proteolysis is critical to these pathways and is often achieved by structural modification, principally the introduction of D-amino acid residues into the elongating peptide. These amino acids are generally formed in situ from their L-stereoisomers by epimerization domains or dual-function condensation/epimerization domains. In singular contrast, the thioesterase domain of nocardicin biosynthesis mediates both the effectively complete L- to D-epimerization of its C-terminal amino acid residue (≥100:1) and hydrolytic product release. We report herein high-resolution crystal structures of the nocardicin thioesterase domain in ligand-free form and reacted with a structurally precise fluorophosphonate substrate mimic that identify the complete peptide binding pocket to accommodate both stereoisomers. These structures combined with additional functional studies provide detailed mechanistic insight into this unique dual-function NRPS domain. |
DOI | 10.1038/s41467-019-11740-6 |
Alternate Journal | Nat Commun |
PubMed ID | 31455765 |
PubMed Central ID | PMC6711958 |
Grant List | R01 AI121072 / AI / NIAID NIH HHS / United States R01 GM116957 / GM / NIGMS NIH HHS / United States AI121072 / / U.S. Department of Health & Human Services | NIH | National Institute of Allergy and Infectious Diseases (NIAID) / GM116957 / / U.S. Department of Health & Human Services | NIH | National Institute of General Medical Sciences (NIGMS) / |
Submitted by bel2021 on September 10, 2019 - 12:07pm