Conformational dynamics of the anthrax lethal factor catalytic center
Georgios A Dalkas1, Christos T Chasapis, Petros V Gkazonis
1Department of Pharmacy, University of Patras, GR-26504 Patras, Greece.
Biochemistry
|December 3, 2010
Summary
Anthrax lethal factor (LF) maintains a compact structure without zinc. Its flexible N-terminal region is key for substrate binding, crucial for understanding anthrax toxin activity.
Area of Science:
- Biochemistry
- Molecular Biology
- Structural Biology
Background:
- Anthrax lethal toxin, a primary virulence factor in anthrax disease, comprises anthrax lethal factor (LF) and protective antigen.
- Anthrax lethal factor (LF) is a zinc-metalloprotease essential for the pathogenesis of anthrax.
Purpose of the Study:
- To investigate the conformational dynamics of the 105 C-terminal residues of the LF catalytic core domain in its apo form (without zinc).
- To understand the structural behavior of LF in the absence of its essential metal cofactor.
Main Methods:
- Solution nuclear magnetic resonance (NMR) spectroscopy was employed to study the protein structure and dynamics.
- In silico computational methods were used to analyze the conformational dynamics of the LF catalytic core domain.
Main Results:
- The 105 C-terminal residues of the LF catalytic core domain adopt a compact structure even in the absence of the Zn(2+) cofactor.
- The N-terminal 40 residues, including metal ligands and substrate/inhibitor recognition sites, exhibit greater flexibility compared to the C-terminal region.
Conclusions:
- The apo form of the LF catalytic core domain maintains a stable, compact structure, indicating inherent stability.
- The flexible N-terminal region is crucial for LF's enzymatic activity, facilitating substrate and inhibitor interactions essential for anthrax pathogenesis.
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