4JLF

Inhibitor resistant (R220A) substitution in the Mycobacterium tuberculosis beta-lactamase

Summary for 4JLF

• Entry DOI: 10.2210/pdb4jlf/pdb
• Related: 2GDN
• Descriptor: Beta-lactamase, PHOSPHATE ION (3 entities in total)
• Functional Keywords: beta-lactams inactivation, tuberculosis, drug design, multi drug resistance, hydrolase
• Biological source: Mycobacterium tuberculosis
• Total number of polymer chains: 1
• Total formula weight: 28661.46

Authors

Hazra, S.,Kurz, S.,Blanchard, J.,Bonomo, R. (deposition date: 2013-03-12, release date: 2013-10-30, Last modification date: 2023-09-20)

Primary citation

Kurz, S.G.,Wolff, K.A.,Hazra, S.,Bethel, C.R.,Hujer, A.M.,Smith, K.M.,Xu, Y.,Tremblay, L.W.,Blanchard, J.S.,Nguyen, L.,Bonomo, R.A.
Can inhibitor-resistant substitutions in the Mycobacterium tuberculosis beta-Lactamase BlaC lead to clavulanate resistance?: a biochemical rationale for the use of beta-lactam-beta-lactamase inhibitor combinations.
Antimicrob.Agents Chemother., 57:6085-6096, 2013

PubMed Abstract: The current emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis calls for novel treatment strategies. Recently, BlaC, the principal β-lactamase of Mycobacterium tuberculosis, was recognized as a potential therapeutic target. The combination of meropenem and clavulanic acid, which inhibits BlaC, was found to be effective against even extensively drug-resistant M. tuberculosis strains when tested in vitro. Yet there is significant concern that drug resistance against this combination will also emerge. To investigate the potential of BlaC to evolve variants resistant to clavulanic acid, we introduced substitutions at important amino acid residues of M. tuberculosis BlaC (R220, A244, S130, and T237). Whereas the substitutions clearly led to in vitro clavulanic acid resistance in enzymatic assays but at the expense of catalytic activity, transformation of variant BlaCs into an M. tuberculosis H37Rv background revealed that impaired inhibition of BlaC did not affect inhibition of growth in the presence of ampicillin and clavulanate. From these data we propose that resistance to β-lactam-β-lactamase inhibitor combinations will likely not arise from structural alteration of BlaC, therefore establishing confidence that this therapeutic modality can be part of a successful treatment regimen against M. tuberculosis.

PubMed: 24060876
DOI: 10.1128/AAC.01253-13

Experimental method

X-RAY DIFFRACTION (2.1 Å)