| Structural highlights
Function
LDT2_MYCTU Generates 3->3 cross-links in peptidoglycan, catalyzing the cleavage of the mDap(3)-D-Ala(4) bond of a tetrapeptide donor stem and the formation of a bond between the carbonyl of mDap(3) of the donor stem and the side chain of mDap(3) of the acceptor stem. Is specific for donor substrates containing a stem tetrapeptide since it cannot use pentapeptide stems.[1]
Publication Abstract from PubMed
Effective treatment of tuberculosis is frequently hindered by the emerging antimicrobial resistance of Mycobacterium tuberculosis. The present study evaluates monocyclic beta-lactam compounds targeting the mycobacterial cell wall remodeling. Novel N-thio-beta-lactams were designed, synthesized, and characterized on the L,D-transpeptidase-2, a validated target in M. tuberculosis. The candidates were evaluated in biochemical assays identifying five compounds presenting target-specific kinetic constants equal or superior to meropenem, a carbapenem currently considered for tuberculosis therapy. Mass spectrometry in line with the crystal structures of five target-ligand complexes revealed that the N-thio-beta-lactams act via an unconventional mode of adduct formation, transferring the thio-residues from the lactam ring to the active-site cysteine of LdtMt2. The resulting stable adducts lead to a long-term inactivation of the target protein. Finally, the candidates were evaluated in vitro against a drug-susceptible and multidrug-resistant clinical isolates of M. tuberculosis, confirming the antimycobacterial effect of these novel compounds.
N-Thio-beta-lactams targeting L,D-transpeptidase-2, with activity against drug-resistant strains of Mycobacterium tuberculosis.,Martelli G, Pessatti TB, Steiner EM, Cirillo M, Caso C, Bisognin F, Landreh M, Monte PD, Giacomini D, Schnell R Cell Chem Biol. 2021 Mar 30. pii: S2451-9456(21)00147-1. doi:, 10.1016/j.chembiol.2021.03.008. PMID:33826941[2]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Cordillot M, Dubee V, Triboulet S, Dubost L, Marie A, Hugonnet JE, Arthur M, Mainardi JL. In vitro cross-linking of Mycobacterium tuberculosis peptidoglycan by L,D-transpeptidases and inactivation of these enzymes by carbapenems. Antimicrob Agents Chemother. 2013 Dec;57(12):5940-5. doi: 10.1128/AAC.01663-13., Epub 2013 Sep 16. PMID:24041897 doi:http://dx.doi.org/10.1128/AAC.01663-13
- ↑ Martelli G, Pessatti TB, Steiner EM, Cirillo M, Caso C, Bisognin F, Landreh M, Monte PD, Giacomini D, Schnell R. N-Thio-beta-lactams targeting L,D-transpeptidase-2, with activity against drug-resistant strains of Mycobacterium tuberculosis. Cell Chem Biol. 2021 Mar 30. pii: S2451-9456(21)00147-1. doi:, 10.1016/j.chembiol.2021.03.008. PMID:33826941 doi:http://dx.doi.org/10.1016/j.chembiol.2021.03.008
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