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Discrete Acyltransferases and Thioesterases in Iso-Migrastatin and Lactimidomycin Biosynthesis

Overview
Journal Biochemistry
Specialty Biochemistry
Date 2024 Feb 12
PMID 38345531
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Abstract

Iso-Migrastatin (iso-MGS) and lactimidomycin (LTM) are glutarimide-containing polyketide natural products (NPs) that are biosynthesized by homologous acyltransferase (AT)-less type I polyketide synthase (PKS) assembly lines. The biological activities of iso-MGS and LTM have inspired numerous efforts to generate analogues via genetic manipulation of their biosynthetic machinery in both native producers and model heterologous hosts. A detailed understanding of the MGS and LTM AT-less type I PKSs would serve to inspire future engineering efforts while advancing the fundamental knowledge of AT-less type I PKS enzymology. The and biosynthetic gene clusters (BGCs) encode for two discrete ATs of the architecture AT-enoylreductase (AT-ER) and AT-type II thioesterase (AT-TE). Herein, we report the functional characterization of the and and the and gene products, revealing that MgsB and LtmB function as type II thioesterases (TEs) and MgsH and LtmH are the dedicated -ATs for the MGS and LTM AT-less type I PKSs. In vivo and in vitro experiments demonstrated that MgsB was devoid of any AT activity, despite the presence of the conserved catalytic triad of canonical ATs. Cross-complementation experiments demonstrated that MgsH and LtmH are functionally interchangeable between the MGS and LTM AT-less type I PKSs. This work sets the stage for future mechanistic studies of AT-less type I PKSs and efforts to engineer the MGS and LTM AT-less type I PKS assembly lines for novel glutarimide-containing polyketides.

References
1.
Nair A, Robson A, Ackrill T, Till M, Byrne M, Back C . Structure and mechanism of a dehydratase/decarboxylase enzyme couple involved in polyketide β-methyl branch incorporation. Sci Rep. 2020; 10(1):15323. PMC: 7501309. DOI: 10.1038/s41598-020-71850-w. View

2.
Englund E, Schmidt M, Nava A, Lechner A, Deng K, Jocic R . Expanding Extender Substrate Selection for Unnatural Polyketide Biosynthesis by Acyltransferase Domain Exchange within a Modular Polyketide Synthase. J Am Chem Soc. 2023; 145(16):8822-8832. PMC: 10141241. DOI: 10.1021/jacs.2c11027. View

3.
Lee S, Liu B, Lee S, Huang S, Shen B, Qian S . Global mapping of translation initiation sites in mammalian cells at single-nucleotide resolution. Proc Natl Acad Sci U S A. 2012; 109(37):E2424-32. PMC: 3443142. DOI: 10.1073/pnas.1207846109. View

4.
Rajski S, Shen B . Multifaceted modes of action for the glutarimide-containing polyketides revealed. Chembiochem. 2010; 11(14):1951-4. PMC: 3517116. DOI: 10.1002/cbic.201000370. View

5.
Hornak V, Abel R, Okur A, Strockbine B, Roitberg A, Simmerling C . Comparison of multiple Amber force fields and development of improved protein backbone parameters. Proteins. 2006; 65(3):712-25. PMC: 4805110. DOI: 10.1002/prot.21123. View