Related Experiment Video
Updated: May 19, 2026
08:41
Identification of Fatty Acids in Bacillus cereus
Published on: December 5, 2016
The tail of mycolic acids
Jeff Zhiqiang Lu1, Sean T Prigge
1Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD 21205, USA.
Chemistry & Biology
|April 19, 2008
Summary
Mycobacterium tuberculosis FabH enzyme binds large substrates via a hydrophobic tunnel. New research shows substrates can access an open enzyme state without fully entering the tunnel, revealing alternative binding mechanisms.
Area of Science:
- Biochemistry
- Structural Biology
- Enzymology
Background:
- The FabH enzyme is crucial for fatty acid biosynthesis in Mycobacterium tuberculosis.
- It is known to bind large substrates within a hydrophobic tunnel.
- Understanding substrate binding is key to developing novel antimycobacterial agents.
Discussion:
- This study investigates the binding mechanism of substrates to the FabH enzyme.
- Reactive chemical probes and X-ray crystallography were employed to visualize substrate interaction.
- The research challenges the established model of substrate threading through the entire tunnel.
Key Insights:
- Substrates can bind to an open conformation of FabH.
- Binding occurs at the tunnel entrance, not requiring full threading.
- This suggests a more flexible substrate interaction than previously understood.
Outlook:
- Further structural and biochemical studies are needed to fully elucidate the dynamic binding process.
- This finding may open new avenues for designing inhibitors that target alternative substrate binding modes.
- Understanding FabH's flexible binding could lead to more effective tuberculosis therapies.
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