1. Academic Validation
  2. 2-Hydroxychalcone is a gonococcal-specific antimicrobial with activity against elongation factor Tu and butanediol dehydrogenase

2-Hydroxychalcone is a gonococcal-specific antimicrobial with activity against elongation factor Tu and butanediol dehydrogenase

  • Life Sci. 2025 Sep 25:381:123994. doi: 10.1016/j.lfs.2025.123994.
Jianglin Zhang 1 Fan Yang 1 Xia Sun 2 Lingyu Gao 1 Jing Yan 1 Xiuxian Chen 3 Yuhua Gu 1 Shuaijie Song 1 Fuliang Hu 3 Xu'ai Lin 1 Simon Duttwyler 4 Hao Cheng 5 Stijn van der Veen 6
Affiliations

Affiliations

  • 1 Department of Infectious Diseases of the Second Affiliated Hospital of Zhejiang University School of Medicine, Department of Microbiology, School of Medicine, Zhejiang University, Hangzhou, China.
  • 2 Department of Infectious Diseases of the Second Affiliated Hospital of Zhejiang University School of Medicine, Department of Microbiology, School of Medicine, Zhejiang University, Hangzhou, China; Zhejiang University-University of Edinburgh Institute, School of Medicine, Zhejiang University, Haining, China.
  • 3 Key laboratory of Silkworm and Bee Resource Utilization and Innovation of Zhejiang Province, College of Animal Sciences, Zhejiang University, Hangzhou, China.
  • 4 Department of Chemistry, Zhejiang University, Hangzhou, China. Electronic address: duttwyler@zju.edu.cn.
  • 5 Department of Dermatology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China. Electronic address: chenghao1@zju.edu.cn.
  • 6 Department of Infectious Diseases of the Second Affiliated Hospital of Zhejiang University School of Medicine, Department of Microbiology, School of Medicine, Zhejiang University, Hangzhou, China; Zhejiang University-University of Edinburgh Institute, School of Medicine, Zhejiang University, Haining, China; State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China. Electronic address: stijnvanderveen@zju.edu.cn.
Abstract

Aims: This study explored botanical extracts to guide discovery of alternative antimicrobials with activity against the multidrug-resistant Bacterial pathogen Neisseria gonorrhoeae.

Materials and methods: In vitro antimicrobial activity was analyzed by agar dilution method and time-kill assays, while in vivo activity was evaluated in a mouse Infection model. The antimicrobial target was identified by pull-down assays and validated by interaction studies with wild-type and targeted mutant proteins.

Key findings: The extract of Chinese Populus spp. propolis (CPP) displayed the most potent antigonococcal activity. Subsequently, galangin was identified as the most active compound in CPP. However, galangin showed no in vivo activity in the mouse Infection model. Screening for active structural analogues of galangin resulted in the identification of 2-hydroxychalcone (2-HC), which showed a minimum inhibitory concentration (MIC) of 8-16 μM, and enhanced gonococcal clearance in the Infection model. Pull-down experiments identified EF-Tu and butanediol dehydrogenase (Bdh) as putative 2-HC targets. Further binding analysis of 2-HC with recombinant purified proteins showed an equilibrium dissociation constant (KD) of 1.28 μM for EF-Tu and 5.97 μM for Bdh. Finally, 2-HC binding pockets on EF-Tu and Bdh were identified by molecular docking studies showing that 2-HC interacted with Glu260 of EF-Tu and Ser273 of Bdh, which was validated by mutagenesis studies. For Bdh, we furthermore demonstrated that 2-HC impacted its enzyme activity with and IC50 of 44-64 μM, resulting in perturbed NAD+/NADH ratios.

Significance: 2-HC displays a bimodal antigonococcal mechanism, making it an interesting candidate for further development as antigonococcal therapy.

Keywords

2-Hydroxychalcone; Butanediol dehydrogenase; Elongation factor Tu; Multidrug-resistance; Neisseria gonorrhoeae; Phytochemicals.

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