Affiliation:
1. Departamento de Ciencias Naturales, Universidad Autónoma Metropolitana Unidad Cuajimalpa, Ciudad de México 05300, Mexico
2. Posgrado en Ciencias Naturales e Ingeniería, Universidad Autónoma Metropolitana Unidad Cuajimalpa, Ciudad de México 05300, Mexico
Abstract
We analyzed the thermal stability of the BstHPr protein through the site-directed point mutation Lys62 replaced by Ala residue using molecular dynamics simulations at five different temperatures: 298, 333, 362, 400, and 450 K, for periods of 1 μs and in triplicate. The results from the mutant thermophilic BstHPrm protein were compared with those of the wild-type thermophilic BstHPr protein and the mesophilic BsHPr protein. Structural and molecular interaction analyses show that proteins lose stability as temperature increases. Mutant and wild-type proteins behave similarly up to 362 K. However, at 400 K the mutant protein shows greater structural instability, losing more buried hydrogen bonds and exposing more of its non-polar residues to the solvent. Therefore, in this study, we confirmed that the salt bridge network of the Glu3–Lys62–Glu36 triad, made up of the Glu3–Lys62 and Glu36–Lys62 ion pairs, provides thermal stability to the thermophilic BstHPr protein.
Funder
Consejo Nacional de Humanidades, Ciencias y Tecnologías (CONAHCyT), México
Reference40 articles.
1. Fersht, A. (1999). Structure and Mechanism in Protein Science: A Guide to Enzyme Catalysis and Protein Folding, W. H. Freeman and Company. [1st ed.].
2. Rangwala, H., and Karypis, G. (2010). Introduction to Protein Structure Prediction: Methods and Algorithms, John Wiley & Sons, Inc.. [1st ed.].
3. Improving Coarse-Grained Models of Protein Folding through Weighting of Polar-Polar/Hydrophobic-Hydrophobic Interactions into Crowded Spaces;J. Mol. Model.,2022
4. Sen, S., and Nilsson, L. (2012). Thermostable Proteins: Structural Stability and Design, Taylor & Francis Group. [1st ed.].
5. Shriver, J.W. (2009). Protein Structure, Stability, and Interactions, Humana Press. [1st ed.].