Bacterial and protozoal enzyme systems

Bacterial and protozoal enzyme systems represent the collective metabolic and redox machinery within microorganisms that are targeted by specific classes of antimicrobial drugs, most notably nitrofurans and nitroimidazoles (Taylor & Francis, 2021). These systems include various enzymes, such as nitroreductases, which are essential for the microbe's normal physiological functions but also serve to activate certain prodrugs (Immunopharmacology and Immunotoxicology, 2021). When these drugs enter the microbial cell, they are reduced by these enzyme systems into highly reactive electrophilic intermediates (StatPearls, 2023). These toxic metabolites then bind to and damage critical cellular components, including DNA, RNA, and proteins, leading to the inhibition of vital processes and eventual cell death (PubChem, 2024). The selective toxicity of these agents relies on the fact that these specific reductive pathways are either unique to or much more active in anaerobic or microaerophilic bacteria and protozoa compared to human cells (NIH, 2023). Consequently, these enzyme systems are pivotal in the treatment of infections caused by pathogens like Helicobacter pylori, Giardia lamblia, and Trichomonas vaginalis (Taylor & Francis, 2021). Understanding these systems is also critical for addressing antimicrobial resistance, which often arises from mutations that decrease the activity of these activating enzymes (PubMed, 2022).

Other names

Microbial enzyme systemsBacterial nitroreductasesProtozoal nitroreductasesMicrobial redox systems

Reductive activation by microbial enzymes (e.g., nitroreductases) into reactive electrophilic intermediates that cause oxidative stress and damage to microbial DNA, RNA, and proteins.