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14:29
Visualization of Bacterial Toxin Induced Responses Using Live Cell Fluorescence Microscopy
Published on: October 1, 2012
Structural and functional features of Streptolysin O
Ashfaq Ahmad1, Ghosia Lutfullah, Roshan Ali
1Centre of Biotechnology and Microbiology, University of Peshawar, Khyber Pukhtun Khwa, Pakistan. ahmad.biotech@yahoo.com
International Journal of Bioinformatics Research and Applications
|November 25, 2011
Summary
Streptolysin O, a toxin damaging cell membranes, has a critical domain (domain 4) important for initial recognition. This domain
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Streptolysin O is a thiol-activated exotoxin that lyses cholesterol-containing cell membranes.
- It is a 63 kDa protein encoded by the slo gene.
Purpose of the Study:
- To analyze the structural domains of Streptolysin O.
- To investigate the role of domain 4 in membrane recognition and toxin activity.
Main Methods:
- Homology modeling was used to analyze the toxin's structure.
- Secondary structure analysis was performed.
Main Results:
- Streptolysin O possesses four distinct domains.
- Domain 4 is crucial for initial membrane recognition and is linked to domain 2 by a glycine linker.
- Domain 4 exhibits a reduced hydrophobic ratio compared to its template, potentially affecting activity at low pH.
Conclusions:
- Domain 4 plays a significant role in Streptolysin O's interaction with target membranes.
- The reduced hydrophobicity of domain 4 may influence the toxin's pH-dependent activity.
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