2. Academic Validation
  3. The enhancement effect of small molecule Lyb24 reveals AzoR as a novel target of polymyxin B

The enhancement effect of small molecule Lyb24 reveals AzoR as a novel target of polymyxin B

  • Biomed Pharmacother. 2023 Nov 8:115856. doi: 10.1016/j.biopha.2023.115856.
Chunxia Hu 1,  Jinyong Zhang 2,  Ruiqin Cui 1,  Shiyi Liu 1,  Ying Huang 3,  Huan Zeng 4,  Shumin Cheng 1,  Guibao Zhou 5,  Jingli Li 6,  Longqin Sun 6,  Yan Zhao 6,  Xiao Wang 5,  Jianhua Liu 3,  Quanming Zou 7,  Wei Huang 8
Affiliations

Affiliations

  • 1 Department of Medical Laboratory, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen 518020, Guangdong, China; Antimicrobial Drug Screening Laboratory, Shenzhen Institute of Respiratory Diseases, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen 518020, Guangdong, China.
  • 2 National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Shapingba District, 400038 Chongqing, China.
  • 3 College of Veterinary Medicine, South China Agricultural University, Guangzhou 510642, Guangdong, China.
  • 4 Antimicrobial Drug Screening Laboratory, Shenzhen Institute of Respiratory Diseases, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen 518020, Guangdong, China; College of Pharmacy, Jinan University, Guangzhou 510632, Guangdong, China.
  • 5 Department of Pharmacy, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen 518020, Guangdong, China.
  • 6 Beijing Qinglian Biotech Co.,Ltd, Haidian District, 100094 Beijing, China.
  • 7 National Engineering Research Center of Immunological Products, Department of Microbiology and Biochemical Pharmacy, College of Pharmacy, Third Military Medical University, Shapingba District, 400038 Chongqing, China. Electronic address: [email protected].
  • 8 Department of Medical Laboratory, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen 518020, Guangdong, China; Antimicrobial Drug Screening Laboratory, Shenzhen Institute of Respiratory Diseases, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen 518020, Guangdong, China; Division of Hepatobiliary and Pancreas surgery, Department of General Surgery, Shenzhen People's Hospital (The Second Clinical Medical College, Jinan University, The First Affiliated Hospital, Southern University of Science and Technology), Shenzhen 518020, Guangdong, China. Electronic address: [email protected].
PMID: 37949698 DOI: 10.1016/j.biopha.2023.115856
Abstract

Given the important role of polymyxin B (PB) in the treatment of drug-resistant Gram-negative Bacterial infections, the emergence of PB resistance poses a serious threat to public health. Adjuvant development is a supplementary strategy that can compensate for the lack of novel Antibiotics by protecting PB. In this study, we found a small molecule named Lyb24 that showed weak Antibacterial activity (minimum inhibitory concentration ≥ 10 μg/ml) but potentiated and revitalized the efficacy of PB against Gram-negative pathogens, including mcr-1- and mgrB-deletion-mediated PB-resistant strains. Our results showed that Lyb24 inhibits the translational levels of genes associated with the modification of lipid A. In addition, Lyb24 increases the permeability, disrupts the integrity and induces the depolarization of the membrane. We further found that both Lyb24 and PB could directly bind to AzoR and inhibit its activity. Structural analysis showed that Lyb24 binds to the isoalloxazine ring of flavin mononucleotide (FMN) through pi-pi stacking and loop η4 of AzoR. A pneumonia model was used to confirm that the activity against clinical PB-resistant Klebsiella pneumoniae was enhanced due to Lyb24 on PB. In conclusion, we provide a potential therapeutic regimen by combining Lyb24 and PB to treat Gram-negative-resistant Bacterial infections. Our findings not only explain the synergistic effect of Lyb24, but also expand our knowledge on the mechanism of action of PB.

Keywords

Antibiotic adjuvant; Drug screening; Gram-negative pathogen; Polymyxin B; Susceptibility.

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