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Updated: Jun 15, 2026
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Antibiotic Dereplication Using the Antibiotic Resistance Platform
Published on: October 17, 2019
Nucleotide selectivity of antibiotic kinases
Tushar Shakya1, Gerard D Wright
1M G DeGroote Institute for Infectious Disease Research, Department of Biochemistry and Biomedical Sciences, McMaster University, Hamilton, Ontario, Canada.
Antimicrobial Agents and Chemotherapy
|March 17, 2010
Summary
Antibiotic phosphotransferases (APHs and MPHs) can use GTP instead of ATP, impacting antimicrobial resistance. Enzyme-specific nucleotide preferences, like GTP-exclusive use by MPH(2')-I, offer new targets for drug development.
Area of Science:
- Biochemistry
- Molecular Biology
- Drug Discovery
Background:
- Antibiotic phosphotransferases (APHs and MPHs) are key enzymes in antimicrobial resistance.
- These enzymes share homology with human Ser/Thr/Tyr kinases, suggesting a common evolutionary origin.
- Recent studies indicate some antibiotic kinases can utilize guanosine triphosphate (GTP) as a phosphate donor, challenging the canonical adenosine triphosphate (ATP) usage.
Purpose of the Study:
- To investigate the nucleotide triphosphate (NTP) preference of three specific antibiotic kinases: APH(3 emp)-IIIa, APH(2 emp'')-Ib, and MPH(2 emp emp')-I.
- To determine how physiological NTP concentrations influence the phosphate donor selection by these enzymes.
- To explore the implications of differential NTP usage for understanding antibiotic resistance evolution and designing targeted inhibitors.
Main Methods:
- Utilized a competitive assay system designed to replicate in vivo nucleotide triphosphate (NTP) concentrations.
- Employed high-performance liquid chromatography (HPLC) for quantitative analysis of reaction products.
- Integrated kinetic analysis and inhibitor studies to further elucidate enzyme mechanisms.
Main Results:
- Under physiological NTP concentrations, APH(3 emp)-IIIa exclusively utilized ATP.
- MPH(2 emp emp')-I exclusively utilized GTP.
- APH(2 emp'')-Ib demonstrated dual specificity, preferentially using GTP over ATP.
Conclusions:
- The observed differential NTP usage among antibiotic kinases suggests distinct evolutionary pathways for antibiotic resistance.
- Understanding these specific nucleotide preferences provides a basis for developing selective inhibitors.
- Targeting these unique enzymatic mechanisms could offer novel strategies to overcome antimicrobial resistance.
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