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Updated: Jun 16, 2026
10:17
A Mass Spectrometry-Based Approach to Identify Phosphoprotein Phosphatases and their Interactors
Published on: April 29, 2022
Auxiliary phosphatases in two-component signal transduction.
1Department of Microbiology and Immunology, University of North Carolina, Chapel Hill, NC 27599-7290, USA. silversr@med.unc.edu
Current Opinion in Microbiology
|February 6, 2010
Summary
Signal termination in two-component systems relies on phosphatases removing phosphoryl groups from response regulators. This review details phosphatase structures, mechanisms, and regulation, aiding in identifying new phosphatase classes.
Area of Science:
- Biochemistry
- Molecular Biology
- Microbiology
Background:
- Two-component systems are crucial for bacterial signal transduction.
- Signal termination involves dephosphorylation of response regulator proteins.
- Phosphatases play a key role in regulating these systems.
Purpose of the Study:
- To review the structures, catalytic mechanisms, and regulation of phosphatases.
- To compare different phosphatase families involved in response regulator dephosphorylation.
- To identify shared features for discovering novel phosphatase classes.
Main Methods:
- Literature review of existing research on response regulator phosphatases.
- Structural and mechanistic analysis of known phosphatase families (CheZ, CheC/CheX/FliY, Spo0E, Rap).
- Comparative analysis of catalytic strategies and regulatory mechanisms.
Main Results:
- CheZ and CheC/CheX/FliY families share catalytic strategies using an amide side chain for water activation.
- Spo0E phosphatases show similarities to chemotaxis phosphatases.
- The mechanism of Rap phosphatases remains unelucidated.
- Conserved features among phosphatase families are identified.
Conclusions:
- Phosphatases utilize diverse structures but conserved catalytic strategies for dephosphorylation.
- Understanding shared features can guide the discovery of new response regulator phosphatases.
- This review provides a foundation for further research into signal termination mechanisms.
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