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Updated: Jun 26, 2026
11:39
Identification of Functional Protein Regions Through Chimeric Protein Construction
Published on: January 8, 2019
Molecular Characterization of OsHAD Phosphoprotein: Expression, Catalytic Properties, and Functional Annotation
Anuradha Pandey1, Aparna Ramakrishnan1, Raja Bhaiyya2
1Department of Biochemistry, Central University of Rajasthan, NH-8, Bandar Sindhri, Ajmer, Rajasthan, 305817, India.
Molecular Biotechnology
|March 3, 2026
Summary
This study characterizes OsHAD-2, a rice haloacid dehalogenase (HAD) family phosphatase. Findings reveal its enzymatic activity and structural properties, advancing understanding of rice phosphatase biology and stress adaptation.
Area of Science:
- Plant molecular biology
- Enzymology
- Biochemistry
Background:
- Phosphatases regulate critical plant cellular processes like signal transduction and stress responses.
- Limited functional and biochemical data exists for many rice phosphatases.
Purpose of the Study:
- To functionally and biochemically characterize OsHAD-2, a previously uncharacterized haloacid dehalogenase (HAD) family phosphatase from Oryza sativa.
- To provide new biochemical and structural insights into HAD-family phosphatases in rice.
Main Methods:
- Heterologous expression of OsHAD-2 in E. coli and purification via GST-affinity chromatography.
- Enzymatic activity assays using p-nitrophenyl phosphate (pNPP).
- Protein characterization using circular dichroism (CD) spectroscopy and mass spectrometry (MS).
- Computational analysis for structural features and stability.
Main Results:
- OsHAD-2 was confirmed as a catalytically active phosphatase with defined optimal conditions, specific activity, and catalytic efficiency.
- CD spectroscopy indicated a stable secondary structure, and MS validated protein identity and purity.
- Computational analysis provided insights into structural features, stability, and potential post-translational modifications.
Conclusions:
- OsHAD-2 is a functional phosphatase, contributing to the understanding of rice phosphatase biology.
- The study provides novel biochemical and structural data for the HAD-family phosphatase, supporting future research on its role in plant physiology and stress adaptation.
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