Discovery of Cephalosporin-3′-Diazeniumdiolates That Show Dual Antibacterial and Antibiofilm Effects against Pseudomonas aeruginosa Clinical Cystic Fibrosis Isolates and Efficacy in a Murine Respiratory Infection Model

Abstract

The formation of biofilms provides a formidable defense for many bacteria against antibiotics and host immune responses. As a consequence, biofilms are thought to be the root cause of most chronic infections, including those occurring on medical indwelling devices, endocarditis, urinary tract infections, diabetic and burn wounds, and bone and joint infections. In cystic fibrosis (CF), chronic Pseudomonas aeruginosa (P. aeruginosa) respiratory infections are the leading cause of morbidity and mortality in adults. Previous studies have shown that many bacteria can undergo a coordinated dispersal event in the presence of low concentrations of nitric oxide (NO), suggesting that NO could be used to initiate biofilm dispersal in chronic infections, enabling clearance of the more vulnerable planktonic cells. In this study, we describe efforts to create “all-in-one” cephalosporin-based NO donor prodrugs (cephalosporin-3′-diazeniumdiolates, C3Ds) that show both direct β-lactam mediated antibacterial activity and antibiofilm effects. Twelve novel C3Ds were synthesized and screened against a panel of P. aeruginosa CF clinical isolates and other human pathogens. The most active compound, AMINOPIP2 ((Z)-1-(4-(2-aminoethyl)­piperidin-1-yl)-2-(((6R,7R)-7-((Z)-2-(2-aminothiazol-4-yl)-2-(((2-carboxypropan-2-yl)­oxy)­imino)­acetamido)-2-carboxy-8-oxo-5-thia-1-azabicyclo­[4.2.0]­oct-2-en-3-yl)­methoxy)­diazene 1-oxide)-ceftazidime 12, showed higher antibacterial potency than its parent cephalosporin and front-line antipseudomonal antibiotic ceftazidime, good stability against β-lactamases, activity against ceftazidime-resistant P. aeruginosa in vitro biofilms, and efficacy equivalent to ceftazidime in a murine P. aeruginosa respiratory infection model. The results support further evaluation of AMINOPIP2-ceftazidime 12 for P. aeruginosa lung infections in CF and a broader study of “all-in-one” C3Ds for other chronic infections.

High-Throughput Approaches for the Identification of Pseudomonas aeruginosa Antivirulents

“…The Kelso lab took the approach of combining ceftazidime (a b-lactam) with a linker that releases two NO molecules, which have been shown to trigger biofilm dispersal, even at low concentrations (76), and a primary amine with weak antimicrobial activity as an "all-in-one" treatment molecule (77). These researchers screened a dozen derivatives of this general class of compounds (cephalosporin-39-diazeniumdiolates).…”

Recent Developments in Nitric Oxide Donors and Delivery for Antimicrobial and Anti-Biofilm Applications

“…Hybrid NO compounds can be designed to improve the specificity of NO-release from small molecule NO donors, or for co-delivery of antimicrobials and NO for synergistic effects [72,76]. A series of cephalosporin-linked diazeniumdiolate NO-donor prodrugs (C3D) has been designed and studied for their antimicrobial and antibiofilm effects [25,[71][72][73][74][75]. These prodrugs consist of a cephalosporin, a class of antibiotics containing a β-lactam ring, linked to a diazeniumdiolate NO donor.…”

The Bactericidal Tandem Drug, AB569: How to Eradicate Antibiotic-Resistant Biofilm Pseudomonas aeruginosa in Multiple Disease Settings Including Cystic Fibrosis, Burns/Wounds and Urinary Tract Infections

“…Other similar NO-generating compounds include sodium nitroprusside (SNP, Barraud et al, 2006 ), S-nitrosoglutathione (GSNO Neufeld and Reynolds, 2016 ), spermine NON-Oate ( Cai and Webb, 2020 ), NO-releasing alginates ( Ahonen et al, 2018 ), and chitosan oligosaccharides ( Reighard et al, 2015 ). Cephalosporin-based NO donor prodrugs (cephalosporin-3’-diazeniumdiolates) not only release NO, but possess direct β-lactam mediated antibacterial activity and antibiofilm effects ( Yepuri et al, 2013 ; Rineh et al, 2020 ). Cephalosporin NO-donor prodrug DEA-C3D (diethylamin-cephalosporin-3′-diazeniumdiolate) has also been shown to disperses PA biofilms formed by cystic CF isolates ( Soren et al, 2020 ).…”