Bacterial and protozoal toxins

Bacterial and protozoal toxins are substances produced by microorganisms that cause damage to host tissues and are central to the pathogenesis of various infectious diseases (StatPearls, 2023). Bacterial toxins are broadly categorized into exotoxins, which are actively secreted proteins, and endotoxins, which are structural components of the bacterial cell wall like lipopolysaccharide (StatPearls, 2023). These molecules exert their effects through diverse mechanisms, such as forming pores in host membranes, enzymatically modifying host proteins via ADP-ribosylation, or overstimulating the immune system as superantigens (Nature Reviews Microbiology, 2010). Protozoal toxins, while less common, include factors like the pore-forming proteins of Entamoeba histolytica or the pro-inflammatory glycosylphosphatidylinositol anchors of Plasmodium species (PubMed, 2001). In therapeutic contexts, these toxins are considered targets for passive immunization strategies, where exogenous antibodies or antitoxins are administered to neutralize the toxin's activity (Journal of Clinical Investigation, 2017). Examples of such therapies include bezlotoxumab for Clostridioides difficile infection and raxibacumab for inhalational anthrax (FDA, 2016). Targeting these toxins is often critical in diseases where the toxin, rather than the organism itself, is the primary driver of morbidity and mortality (Clinical Microbiology Reviews, 2019).

Other names

Microbial toxinsExotoxins and endotoxinsPathogenic virulence factorsBacterial and protozoan virulence factors

Neutralization of toxin activity by preventing binding to host cell receptors or inhibiting enzymatic activity.