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Generation of Null Mutants to Elucidate the Role of Bacterial Glycosyltransferases in Bacterial Motility
Published on: March 11, 2022
Bacterial toxin and effector glycosyltransferases
1Gamaleya Research Institute, Moscow 123098, Russia.
Biochimica Et Biophysica Acta
|August 4, 2009
Summary
Bacterial glucosylating cytotoxins from Clostridium and Legionella modify host proteins. These toxins, targeting Rho/Ras proteins and elongation factor eEF1A, disrupt cellular functions and cause disease.
Area of Science:
- Microbiology
- Molecular Biology
- Toxicology
Background:
- Clostridial glucosylating cytotoxins (e.g., C. difficile toxins A/B, C. novyi alpha-toxin, C. sordellii lethal toxin) are key virulence factors in human diseases.
- These toxins target Rho/Ras proteins, essential molecular switches, by mono-O-glucosylation at a threonine residue, impairing their function.
Purpose of the Study:
- To discuss recent findings on the structures, functions, and biological roles of bacterial toxin glucosyltransferases.
- To highlight the newly identified glucosyltransferases from Legionella pneumophila and their distinct targets.
Main Methods:
- Comparative analysis of toxin structures and enzymatic mechanisms.
- Functional studies on host-pathogen interactions.
- Biochemical assays to characterize glycosylation activities.
Main Results:
- Clostridial toxins glucosylate Rho/Ras proteins, disrupting actin cytoskeleton regulation.
- Legionella glucosyltransferases modify elongation factor eEF1A at a serine residue.
- This modification by Legionella enzymes inhibits host cell protein synthesis.
Conclusions:
- Bacterial glucosylating toxins represent a significant class of virulence factors with diverse targets and mechanisms.
- Understanding these toxins' structures and functions is crucial for developing therapeutic strategies against bacterial infections.
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