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Updated: Jul 30, 2026
08:47
Lighting Up the Pathways to Caspase Activation Using Bimolecular Fluorescence Complementation
Published on: March 5, 2018
[W206R]-procaspase 3: an inactivatable substrate for caspase 8
K B Rank1, A M Mildner, J W Leone
1Pharmacia Corporation, Kalamazoo, Michigan 49007, USA.
Protein Expression and Purification
|July 5, 2001
Summary
Researchers engineered a mutant procaspase 3 (m-pro3) that is processed by caspase 8 but remains inactive due to a W206R mutation. This inactive enzyme is useful for studying caspase 8 inhibitors and for structural analysis.
Area of Science:
- Biochemistry
- Molecular Biology
- Enzymology
Background:
- Caspase 3 is a key executioner caspase in apoptosis.
- Understanding caspase processing and activity is crucial for studying cell death pathways.
Purpose of the Study:
- To clone and express a soluble proform of human caspase 3.
- To engineer a mutant procaspase 3 (m-pro3) for specific applications.
Main Methods:
- Engineered expression of a soluble proform of human caspase 3 with modifications.
- Purification using immobilized metal-ion affinity chromatography.
- Biochemical assays involving incubation with recombinant human caspase 8 and amino-terminal sequencing.
Main Results:
- Successfully cloned and expressed a 32-kDa procaspase 3 precursor.
- Caspase 8 specifically cleaved procaspase 3 at Asp175-Ser176 and partially at Asp28-Ser29.
- The processed caspase 3 was inactive due to a W206R mutation, creating m-pro3.
Conclusions:
- The engineered m-pro3 serves as a valuable tool for evaluating caspase 8 inhibitors.
- m-pro3 can be utilized as a source of proenzyme for crystallographic studies.
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