A Fluorescence-Based Assay for Screening β-Lactams Targeting the Mycobacterium tuberculosis Transpeptidase LdtMt2.

Abstract

Mycobacterium tuberculosis l,d-transpeptidases (Ldts), which are involved in cell-wall biosynthesis, have emerged as promising targets for the treatment of tuberculosis. However, an efficient method for testing inhibition of these enzymes is not currently available. We present a fluorescence-based assay for LdtMt2 , which is suitable for high-throughput screening. Two fluorogenic probes were identified that release a fluorophore upon reaction with LdtMt2 , thus making it possible to assess the availability of the catalytic site in the presence of inhibitors. The assay was applied to a panel of β-lactam antibiotics and related inhibitors; the results validate observations that the (carba)penem subclass of β-lactams are more potent Ldt inhibitors than other β-lactam classes, though unexpected variations in potency were observed. The method will enable systematic structure-activity relationship studies on Ldts, thereby facilitating the identification of new antibiotics active against M. tuberculosis.

• Authors: Mariska de Munnik, Christopher T Lohans, Gareth W Langley, Corentin Bon, Jürgen Brem, Christopher J Schofield
• Journal: Chembiochem : a European journal of chemical biology (Chembiochem) Vol. 21 Issue 3 Pg. 368-372 (02 03 2020) ISSN: 1439-7633 [Electronic] Germany
• PMID: 31322798 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Chemical References

• Anti-Bacterial Agents
• Enzyme Inhibitors
• Fluorescent Dyes
• beta-Lactams
• Peptidyl Transferases

Topics

• Anti-Bacterial Agents (chemistry, pharmacology)
• Enzyme Inhibitors (chemistry, pharmacology)
• Fluorescence
• Fluorescent Dyes (chemistry, pharmacology)
• High-Throughput Screening Assays
• Microbial Sensitivity Tests
• Molecular Structure
• Mycobacterium tuberculosis (drug effects, metabolism)
• Peptidyl Transferases (antagonists & inhibitors, metabolism)
• beta-Lactams (chemistry, pharmacology)