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T4 Bacteriophage and E. coli Interaction in the Murine Intestine: A Prototypical Model for Studying Host-Bacteriophage Dynamics In Vivo
Published on: January 26, 2024
Lessons from the lysozyme of phage T4
Walter A Baase1, Lijun Liu, Dale E Tronrud
1Institute of Molecular Biology, 1229 University of Oregon, Eugene, Oregon 97403-1229, USA.
Protein Science : a Publication of the Protein Society
|January 23, 2010
Summary
Studies on T4 phage lysozyme reveal key insights into protein stability and folding. The Ser 117 --> Val mutant shows a significant melting temperature increase, highlighting hydrophobic stabilization and improved van der Waals contacts.
Area of Science:
- Biochemistry
- Structural Biology
- Protein Engineering
Background:
- T4 phage lysozyme is a model system for studying protein folding, stability, and structure-function relationships.
- Understanding protein stability is crucial for protein engineering and drug design.
Purpose of the Study:
- To provide a comprehensive review of T4 phage lysozyme variants.
- To tabulate data on melting temperatures, crystallographic data, and Protein Data Bank (PDB) access codes for characterized mutants.
- To elucidate the structural and energetic factors governing protein stability.
Main Methods:
- Analysis of existing literature on T4 phage lysozyme mutants.
- Compilation of experimental data including melting temperatures (Tm) and crystallographic information.
- Review of structural data from X-ray crystallography and Nuclear Magnetic Resonance (NMR) spectroscopy.
Main Results:
- The Ser 117 --> Val mutant exhibits the largest Tm increase (5.1°C) due to hydrophobic stabilization and elimination of unfavorable contacts.
- Destabilizing substitutions can decrease Tm by approximately 20°C.
- The energetic cost of cavity creation and hydrophobic effects are supported by studies on T4 lysozyme and bacteriorhodopsin.
- Ligand binding in the L99A mutant involves conformational changes in Helix F, supported by crystallographic and NMR data.
- 43 nonisomorphous crystal forms of mutants and 3 for dimers were obtained, with P2(1)2(1)2(1) and P2(1) being the most frequent space groups.
Conclusions:
- Protein stability is influenced by a balance of hydrophobic interactions, hydrogen bonding, and van der Waals forces.
- Mutagenesis studies provide valuable insights into protein structure-stability relationships.
- T4 lysozyme serves as a robust model for understanding fundamental principles of protein science.
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