Covalent inhibitors of LgtC: A blueprint for the discovery of non-substrate-like inhibitors for bacterial glycosyltransferases

Abstract

. Covalent inhibitors of LgtC: a blueprint for the discovery of non-substrate-like inhibitors for bacterial glycosyltransferases. Bioorganic and Medicinal Chemistry, 25(12), 3182-3194. https://doi.org/10.1016/j.bmc.2017.04.006Citing this paper Please note that where the full-text provided on King's Research Portal is the Author Accepted Manuscript or Post-Print version this may differ from the final Published version. If citing, it is advised that you check and use the publisher's definitive version for pagination, volume/issue, and date of publication details. And where the final published version is provided on the Research Portal, if citing you are again advised to check the publisher's website for any subsequent corrections. General rightsCopyright and moral rights for the publications made accessible in the Research Portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognize and abide by the legal requirements associated with these rights.•Users may download and print one copy of any publication from the Research Portal for the purpose of private study or research.•You may not further distribute the material or use it for any profit-making activity or commercial gain •You may freely distribute the URL identifying the publication in the Research Portal Take down policyIf you believe that this document breaches copyright please contact librarypure@kcl.ac.uk providing details, and we will remove access to the work immediately and investigate your claim. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.-1 - data reveals that non-catalytic cysteines are a common motif in the active site of many bacterial glycosyltransferases. Our results can therefore serve as a blueprint for the rational design of non-substrate-like, covalent inhibitors against a broad range of other bacterial glycosyltransferases.-3 -

Structure-activity relationships in a new class of non-substrate-like covalent inhibitors of the bacterial glycosyltransferase LgtC

“…In contrast, compounds with different modifications at the 3-or 4position of the 2-phenyl ring (7f, 7g, and 10) maintained similar inhibitory activity as the parent 7b. These general SAR trends are consistent with previous results from docking experiments, which indicated that the 2-phenyl ring is oriented away from the binding pocket towards solvent [13]. This proposed binding mode can explain the observed tolerance towards different substituents in this position.…”

“…Kinetic parameters for covalent inhibition of LgtC by selected 5-CF 3 pyrazol-3-ones. 1 [13] in these experiments. NTHi strain R2866 was first isolated by Nizet from the blood of children with a meningitis infection [20].…”

“…In the present study, we have systematically explored structural modifications around the pyrazol-3-one scaffold. Starting from prototype inhibitor 1 [13], we first designed and synthesised analogues with various substituents at the 5-position of the pyrazol-3-one scaffold (Fig. 2).…”

“…In this enzymecoupled assay, calf intestinal phosphatase (CIP) is used to selectively and quantitatively release inorganic phosphate (P i ) from UDP, the secondary product of the LgtC reaction, followed by quantification of P i with Malachite Green. Because of the covalent mode of action previously observed in this inhibitor series [13], we preincubated the enzyme with inhibitor prior to starting the enzymatic reaction.…”

“…We have recently discovered a novel class of non-substrate-like LgtC inhibitors based on a pyrazol-3-one scaffold (Fig. 2) [13]. These inhibitors behave as substrate mimics and react covalently, at their Michael acceptor system, with a non-catalytic cysteine in the LgtC active site [13].…”