TY - JOUR
T1 - β-Lactone formation during product release from a nonribosomal peptide synthetase
AU - Schaffer, Jason E.
AU - Reck, Margaret R.
AU - Prasad, Neha K.
AU - Wencewicz, Timothy A.
N1 - Funding Information:
This work was supported with start-up funds provided by Washington University in St. Louis and the Research Corporation for Science Advancement through a Cottrell Scholar award to T.A.W.
Publisher Copyright:
© 2017 Nature America, Inc., part of Springer Nature. All rights reserved.
PY - 2017/7/1
Y1 - 2017/7/1
N2 - Nonribosomal peptide synthetases (NRPSs) are multidomain modular biosynthetic assembly lines that polymerize amino acids into a myriad of biologically active nonribosomal peptides (NRPs). NRPS thioesterase (TE) domains employ diverse release strategies for off-loading thioester-tethered polymeric peptides from termination modules typically via hydrolysis, aminolysis, or cyclization to provide mature antibiotics as carboxylic acids/esters, amides, and lactams/lactones, respectively. Here we report the enzyme-catalyzed formation of a highly strained β-lactone ring during TE-mediated cyclization of a β-hydroxythioester to release the antibiotic obafluorin (Obi) from an NRPS assembly line. The Obi NRPS (ObiF) contains a type I TE domain with a rare catalytic cysteine residue that plays a direct role in β-lactone ring formation. We present a detailed genetic and biochemical characterization of the entire Obi biosynthetic gene cluster in plant-associated Pseudomonas fluorescens ATCC 39502 that establishes a general strategy for β-lactone biogenesis.
AB - Nonribosomal peptide synthetases (NRPSs) are multidomain modular biosynthetic assembly lines that polymerize amino acids into a myriad of biologically active nonribosomal peptides (NRPs). NRPS thioesterase (TE) domains employ diverse release strategies for off-loading thioester-tethered polymeric peptides from termination modules typically via hydrolysis, aminolysis, or cyclization to provide mature antibiotics as carboxylic acids/esters, amides, and lactams/lactones, respectively. Here we report the enzyme-catalyzed formation of a highly strained β-lactone ring during TE-mediated cyclization of a β-hydroxythioester to release the antibiotic obafluorin (Obi) from an NRPS assembly line. The Obi NRPS (ObiF) contains a type I TE domain with a rare catalytic cysteine residue that plays a direct role in β-lactone ring formation. We present a detailed genetic and biochemical characterization of the entire Obi biosynthetic gene cluster in plant-associated Pseudomonas fluorescens ATCC 39502 that establishes a general strategy for β-lactone biogenesis.
UR - http://www.scopus.com/inward/record.url?scp=85021167873&partnerID=8YFLogxK
U2 - 10.1038/nchembio.2374
DO - 10.1038/nchembio.2374
M3 - Article
C2 - 28504677
AN - SCOPUS:85021167873
SN - 1552-4450
VL - 13
SP - 737
EP - 744
JO - Nature Chemical Biology
JF - Nature Chemical Biology
IS - 7
ER -