Dataset Information

High-throughput screening of small-molecules libraries identified antibacterials against clinically relevant multidrug-resistant A. baumannii and K. pneumoniae.

ABSTRACT:

Background

The current pipeline for new antibiotics fails to fully address the significant threat posed by drug-resistant Gram-negative bacteria that have been identified by the World Health Organization (WHO) as a global health priority. New antibacterials acting through novel mechanisms of action are urgently needed. We aimed to identify new chemical entities (NCEs) with activity against Klebsiella pneumoniae and Acinetobacter baumannii that could be developed into a new treatment for drug-resistant infections.

Methods

We developed a high-throughput phenotypic screen and selection cascade for generation of hit compounds active against multidrug-resistant (MDR) strains of K. pneumoniae and A. baumannii. We screened compound libraries selected from the proprietary collections of three pharmaceutical companies that had exited antibacterial drug discovery but continued to accumulate new compounds to their collection. Compounds from two out of three libraries were selected using "eNTRy rules" criteria associated with increased likelihood of intracellular accumulation in Escherichia coli.

Findings

We identified 72 compounds with confirmed activity against K. pneumoniae and/or drug-resistant A. baumannii. Two new chemical series with activity against XDR A. baumannii were identified meeting our criteria of potency (EC₅₀ ≤50 μM) and absence of cytotoxicity (HepG2 CC₅₀ ≥100 μM and red blood cell lysis HC₅₀ ≥100 μM). The activity of close analogues of the two chemical series was also determined against A. baumannii clinical isolates.

Interpretation

This work provides proof of principle for the screening strategy developed to identify NCEs with antibacterial activity against multidrug-resistant critical priority pathogens such as K. pneumoniae and A. baumannii. The screening and hit selection cascade established here provide an excellent foundation for further screening of new compound libraries to identify high quality starting points for new antibacterial lead generation projects.

Funding

BMBF and GARDP.

SUBMITTER: Blasco B

PROVIDER: S-EPMC10963893 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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Publications

High-throughput screening of small-molecules libraries identified antibacterials against clinically relevant multidrug-resistant A. baumannii and K. pneumoniae.

Blasco Benjamin B Jang Soojin S Terauchi Hiroki H Kobayashi Naoki N Suzuki Shuichi S Akao Yuichiro Y Ochida Atsuko A Morishita Nao N Takagi Terufumi T Nagamiya Hiroyuki H Suzuki Yamato Y Watanabe Toshiaki T Lee Hyunjung H Lee Sol S Shum David D Cho Ahreum A Koh Dahae D Park Soonju S Lee Honggun H Kim Kideok K Ropponen Henni-Karoliina HK Augusto da Costa Renata Maria RM Dunn Steven S Ghosh Sunil S Sjö Peter P Piddock Laura J V LJV

EBioMedicine 20240322

<h4>Background</h4>The current pipeline for new antibiotics fails to fully address the significant threat posed by drug-resistant Gram-negative bacteria that have been identified by the World Health Organization (WHO) as a global health priority. New antibacterials acting through novel mechanisms of action are urgently needed. We aimed to identify new chemical entities (NCEs) with activity against Klebsiella pneumoniae and Acinetobacter baumannii that could be developed into a new treatment for ...[more]

PMID: 38520916

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Dataset Information

High-throughput screening of small-molecules libraries identified antibacterials against clinically relevant multidrug-resistant A. baumannii and K. pneumoniae.

Background

Methods

Findings

Interpretation

Funding

Publications

High-throughput screening of small-molecules libraries identified antibacterials against clinically relevant multidrug-resistant A. baumannii and K. pneumoniae.

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