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Aip1p Dynamics Are Altered by the R256H Mutation in Actin
Published on: July 30, 2014
Actin as target for modification by bacterial protein toxins
Klaus Aktories1, Alexander E Lang, Carsten Schwan
1Institut für Experimentelle und Klinische Pharmakologie und Toxikologie, Albert-Ludwigs-Universität Freiburg, Germany. klaus.aktories@pharmakol.uni-freiburg.de
The FEBS Journal
|April 7, 2011
Summary
Bacterial toxins target the actin cytoskeleton by modifying actin molecules. These toxins inhibit or promote actin polymerization, or crosslink actin to form aggregates, impacting cellular functions.
Area of Science:
- Microbiology
- Cell Biology
- Biochemistry
Background:
- Bacterial protein toxins and effectors frequently target the host cell's actin cytoskeleton.
- The actin cytoskeleton is crucial for various cellular processes, making it a common target for bacterial virulence factors.
Purpose of the Study:
- To categorize bacterial toxins and effectors that directly modify actin molecules.
- To discuss novel findings regarding these actin-targeting bacterial agents.
Main Methods:
- Classification of bacterial toxins/effectors based on their mechanism of actin modification.
- Review and discussion of recent scientific findings on these toxins.
Main Results:
- Identified three distinct groups of bacterial toxins/effectors that modify actin.
- Group 1: ADP-ribosylation at Arg-177 inhibits actin polymerization (e.g., Clostridium botulinum C2 toxin, Salmonella enterica SpvB).
- Group 2: ADP-ribosylation at Thr-148 promotes actin polymerization (e.g., Photorhabdus luminescens Tc toxin).
- Group 3: Catalyzes actin crosslinking, forming oligomers and blocking polymerization (e.g., Vibrio cholerae RTX toxin).
Conclusions:
- Bacterial pathogens employ diverse strategies to manipulate the actin cytoskeleton.
- Understanding these mechanisms is key to developing countermeasures against bacterial infections.
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