Sulfonamidoboronic Acids as "Cross-Class" Inhibitors of an Expanded-Spectrum Class C Cephalosporinase, ADC-33, and a Class D Carbapenemase, OXA-24/40: Strategic Compound Design to Combat Resistance in Acinetobacter baumannii .
Maria Luisa IntrovigneTrevor J BeardsleyMicah C FernandoDavid A LeonardBradley J WallarSusan D RudinMagdalena A TaracilaPhilip N RatherJennifer M ColquhounShaina SongFrancesco FiniKristine M HujerAndrea M HujerFabio PratiRachel A PowersRobert A BonomoEmilia CaselliPublished in: Antibiotics (Basel, Switzerland) (2023)
Acinetobacter baumannii is a Gram-negative organism listed as an urgent threat pathogen by the World Health Organization (WHO). Carbapenem-resistant A. baumannii (CRAB), especially, present therapeutic challenges due to complex mechanisms of resistance to β -lactams. One of the most important mechanisms is the production of β -lactamase enzymes capable of hydrolyzing β -lactam antibiotics. Co-expression of multiple classes of β -lactamases is present in CRAB; therefore, the design and synthesis of "cross-class" inhibitors is an important strategy to preserve the efficacy of currently available antibiotics. To identify new, nonclassical β -lactamase inhibitors, we previously identified a sulfonamidomethaneboronic acid CR167 active against Acinetobacter -derived class C β -lactamases (ADC-7). The compound demonstrated affinity for ADC-7 with a K i = 160 nM and proved to be able to decrease MIC values of ceftazidime and cefotaxime in different bacterial strains. Herein, we describe the activity of CR167 against other β -lactamases in A. baumannii : the cefepime-hydrolysing class C extended-spectrum β -lactamase (ESAC) ADC-33 and the carbapenem-hydrolyzing OXA-24/40 (class D). These investigations demonstrate CR167 as a valuable cross-class (C and D) inhibitor, and the paper describes our attempts to further improve its activity. Five chiral analogues of CR167 were rationally designed and synthesized. The structures of OXA-24/40 and ADC-33 in complex with CR167 and select chiral analogues were obtained. The structure activity relationships (SARs) are highlighted, offering insights into the main determinants for cross-class C/D inhibitors and impetus for novel drug design.
Keyphrases
- acinetobacter baumannii
- multidrug resistant
- gram negative
- drug resistant
- klebsiella pneumoniae
- pseudomonas aeruginosa
- escherichia coli
- diffusion weighted imaging
- diffusion weighted
- molecular docking
- emergency department
- computed tomography
- ionic liquid
- poor prognosis
- magnetic resonance imaging
- mass spectrometry
- capillary electrophoresis
- contrast enhanced