Impacts of the charged residues mutation S48E/N62H on the thermostability and unfolding behavior of cold shock protein: insights from molecular dynamics simulation with Go model.
J Mol Model
; 22(4): 91, 2016 Apr.
Article
em En
| MEDLINE
| ID: mdl-27021210
ABSTRACT
The cold shock protein from the hyperthermophile Thermotoga maritima (Tm-Csp) exhibits significantly higher thermostability than its homologue from the thermophile Bacillus caldolyticus (Bc-Csp). Experimental studies have shown that the electrostatic interactions unique to Tm-Csp are responsible for improving its thermostability. In the present work, the favorable charged residues in Tm-Csp were grafted into Bc-Csp by a double point mutation of S48E/N62H, and the impacts of the mutation on the thermostability and unfolding/folding behavior of Bc-Csp were then investigated by using a modified Go model, in which the electrostatic interactions between charged residues were considered in the model. Our simulation results show that this Tm-Csp-like charged residue mutation can effectively improve the thermostability of Bc-Csp without changing its two-state folding mechanism. Besides that, we also studied the unfolding kinetics and unfolding/folding pathway of the wild-type Bc-Csp and its mutant. It is found that this charged residue mutation obviously enhanced the stability of the C-terminal region of Bc-Csp, which decreases the unfolding rate and changes the unfolding/folding pathway of the protein. Our studies indicate that the thermostability, unfolding kinetics and unfolding/folding pathway of Bc-Csp can be artificially changed by introducing Tm-Csp-like favorable electrostatic interactions into Bc-Csp.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
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Substituição de Aminoácidos
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Thermotoga maritima
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Simulação de Dinâmica Molecular
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Proteínas de Choque Térmico
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Mutação
Idioma:
En
Revista:
J Mol Model
Ano de publicação:
2016
Tipo de documento:
Article