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Type II secretion: the substrates that won't go away.
Arnaud Rondelet1, Guy Condemine
1Université de Lyon, F69003, Université Lyon 1, F69622, INSA-Lyon, F69621, CNRS UMR5240, Microbiologie Adaptation et Pathogénie, 10 rue Dubois, Bât. Lwoff, 69622 Villeurbanne, France.
Research in Microbiology
|March 30, 2013
Summary
Type II secretion systems (T2SSs) secrete proteins into the medium or to the bacterial surface. New research explores how T2SSs handle membrane-anchored proteins, a previously overlooked area.
Area of Science:
- Microbiology
- Molecular Biology
- Bacterial Cell Biology
Background:
- Type II secretion systems (T2SSs) are crucial pathways for protein export in bacteria.
- T2SSs typically secrete folded proteins into the extracellular environment or to the bacterial cell surface.
- The mechanisms by which T2SSs interact with and secrete membrane-anchored proteins remain largely unknown.
Purpose of the Study:
- To investigate the mechanisms of Type II secretion systems (T2SSs) in handling membrane-anchored proteins.
- To highlight the significance of T2SS substrates that remain associated with the bacterial surface.
- To address the current knowledge gap regarding T2SS-mediated secretion of membrane proteins.
Main Methods:
- Proteomic analysis to identify T2SS substrates.
- Bacterial genetics and molecular biology techniques to study protein localization and secretion.
- Biochemical assays to characterize protein-substrate interactions.
Main Results:
- T2SSs can secrete proteins that remain bound to or anchored at the bacterial surface.
- These systems are capable of targeting complex proteins, including those with cofactors or requiring periplasmic folding.
- The study identifies membrane-anchored proteins as a class of T2SS substrates that have been previously overlooked.
Conclusions:
- Type II secretion systems (T2SSs) play a role in the surface display of various proteins, including membrane-anchored ones.
- Understanding T2SSs' interaction with membrane proteins is essential for comprehending bacterial surface protein architecture.
- Advancements in proteomic technologies are expected to facilitate the discovery and characterization of these novel T2SS substrates.
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