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Published on: July 16, 2017
MPKaDB: A pKadatabase for exploring pH dependence in membrane proteins
Jiahao He1, Yansheng Chen2, Jinxi Wu1
1College of Computer Engineering, Jimei University, Xiamen 361021, China.
Abstract:
The biological activities of many membrane proteins are pH-regulated, yet mapping their pH dependence experimentally is slow and expensive. In this work, we present MPKaDB (http://computbiophys.com/DeepKa/mpkadb), a comprehensive pKadatabase for membrane proteins that instantly decode the protonation states of ionizable residues under a specified pH. Leveraging MPKaDB, we performed pH-coupled electrostatic characterization of transmembrane proteins. To facilitate use, a user-friendly search engine was developed to retrieve proteins of interest and return residue-specific pKavalues, isoelectric points (pI) at cytoplasmic and extra-cytoplasmic faces, and automated screenings of active site residues. In the end, two case studies were proposed to demonstrate how pKa's from MPKaDB could be applied to exploring the pH-dependent relationship between membrane protein structure and function.
Insights
MPKaDB is a new database that quickly predicts the protonation states of membrane proteins. This tool helps researchers understand how pH affects protein function, saving time and resources.
Area of Science:
- Computational biology
- Structural biology
- Biophysics
Background:
- Membrane protein functions are often regulated by pH.
- Experimental determination of pH dependence is time-consuming and costly.
Purpose of the Study:
- To introduce MPKaDB, a comprehensive database for membrane protein pKa values.
- To enable rapid prediction of residue protonation states at specific pH values.
- To facilitate pH-coupled electrostatic characterization of membrane proteins.
Main Methods:
- Development of MPKaDB, a pKa database for membrane proteins.
- Implementation of a user-friendly search engine for protein retrieval.
- Calculation of residue-specific pKa values, isoelectric points (pI), and active site analysis.
Main Results:
- MPKaDB provides instant decoding of ionizable residue protonation states.
- The database offers pKa values, pI (cytoplasmic and extra-cytoplasmic), and active site screenings.
- Case studies demonstrate the application of MPKaDB in exploring pH-dependent protein function.
Conclusions:
- MPKaDB significantly accelerates the study of pH-dependent membrane protein behavior.
- The database serves as a valuable resource for understanding membrane protein structure-function relationships.
- MPKaDB aids in the efficient characterization of membrane proteins.
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