Related Experiment Video
Updated: Aug 15, 2026

Visualization of Bacterial Toxin Induced Responses Using Live Cell Fluorescence Microscopy
Published on: October 1, 2012
Human mononuclear leukocyte transglutaminase activity is enhanced by streptococcal erythrogenic toxin and a
Abstract:
Transglutaminase activity in human peripheral lymphocytes is enhanced after incubation of the cells with concanavalin A. Streptococcal proliferative factor toxin (erythrogenic toxin) from Streptococcus pyogenes and Toxic shock syndrome toxin from Staphylococcus aureus were purified and tested for their ability to enhance transglutaminase activity. Mononuclear leukocyte transglutaminase activity was enhanced 3-5-fold 30 min after incubation with either toxin. Enhancement occurred only when toxin was incubated with intact cells; addition of toxin to cell lysates was without effect. Transglutaminase was not measurable extracellularly. Histamine and dansyl cadaverine, competitive substrates for transglutaminase, inhibited [3H]putrescine incorporation into casein and [3H]thymidine incorporation into DNA. Incubation of lymphocytes with cycloheximide and either toxin or concanavalin A did not inhibit enzyme activity. These bacterial toxins, like phytomitogens, may perturb the cellular membrane and mediate their effect by transglutaminase-mediated cross-linking of membrane proteins.
More Related Videos
09:25Implementation of a Permeable Membrane Insert-based Infection System to Study the Effects of Secreted Bacterial Toxins on Mammalian Host Cells
Published on: August 19, 2016
14:05Morphological and Compositional Analysis of Neutrophil Extracellular Traps Induced by Microbial and Chemical Stimuli
Published on: November 4, 2022