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Increase of enzyme activity through specific covalent modification with fragments
John F Darby1, Masakazu Atobe1,2, James D Firth1
1Department of Chemistry , University of York , Heslington , York , YO10 5DD , UK .
Chemical Science
|November 23, 2017
Summary
Covalently attaching small molecules to enzymes can significantly boost their activity, up to 35-fold. This enzyme activation method also enhances susceptibility to inhibitors, offering new ways to control cellular functions.
Area of Science:
- Biochemistry
- Enzymology
- Chemical Biology
Background:
- Enzyme activity modulation is crucial for understanding cellular functions and has broad applications.
- Small molecules can influence enzyme activity, but controlling this interaction precisely is challenging.
Purpose of the Study:
- To investigate covalent tethering of small molecules to enhance enzyme catalytic activity.
- To explore how tethering affects enzyme efficiency and inhibitor susceptibility.
- To understand structure-activity relationships in enzyme-fragment conjugates.
Main Methods:
- Utilized Michael-addition chemistry for covalent tethering of small molecule fragments to a bacterial glycoside hydrolase (BtGH84).
- Assessed changes in catalytic efficiency (kcat/KM) of the enzyme-fragment conjugate.
- Employed structure-guided modifications to analyze fragment-enzyme interactions and their impact on activation.
Main Results:
- Covalent tethering increased catalytic activity up to 35-fold compared to the free enzyme.
- The enzyme-fragment conjugate exhibited constitutive activation and altered inhibitor susceptibility.
- Specific interactions between the tethered fragment and the enzyme were shown to modulate the degree of activation.
Conclusions:
- Covalent tethering is an effective strategy for enzyme activation, significantly improving catalytic efficiency.
- This approach can create enzyme-fragment conjugates with tunable properties, including altered inhibitor responses.
- The findings suggest a versatile method for enzyme engineering to enhance catalytic power or modulate drug interactions.
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