| Texto completo | |
| Autor(es): |
Oliveira, Ivan P.
;
Martinez, Leandro
Número total de Autores: 2
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Physical Chemistry Chemical Physics; v. 18, n. 31, p. 21797-21808, AUG 31 2016. |
| Citações Web of Science: | 5 |
| Resumo | |
Increasing the stability of proteins is important for their application in industrial processes. In the intracellular environment many small molecules, called osmolytes, contribute to protein stabilization under physical or chemical stress. Understanding the nature of the interactions of these osmolytes with proteins can help the design of solvents and mutations to increase protein stability in extracellular media. One of the most common stabilizing osmolyes is sorbitol and one of the most common chemical denaturants is urea. In this work, we use molecular dynamics simulations to obtain a detailed picture of the solvation of the Burkholderia cepacia lipase (BCL) in the presence of the protecting osmolyte sorbitol and of the urea denaturant. We show that both sorbitol and urea compete with water for interactions with the protein surface. Overall, sorbitol promotes the organization of water in the first solvation shell and displaces water from the second solvation shell, while urea causes opposite effects. These effects are, however, highly heterogeneous among residue types. For instance, the depletion of water from the first protein solvation shell by urea can be traced down essentially to the side chain of negatively charged residues. The organization of water in the first solvation shell promoted by sorbitol occurs at polar (but not charged) residues, where the urea effect is minor. By contrast, sorbitol depletes water from the second solvation shell of polar residues, while urea promotes water organization at the same distances. The interactions of urea with negatively charged residues are insensitive to the presence of sorbitol. This osmolyte removes water and urea particularly from the second solvation shell of polar and non-polar residues. In summary, we provide a comprehensive description of the diversity of protein-solvent interactions, which can guide further investigations on the stability of proteins in non-conventional media, and assist solvent and protein design. (AU) | |
| Processo FAPESP: | 10/16947-9 - Estrutura, dinâmica e função em proteínas: simulação computacional e desenvolvimento de algoritmos |
| Beneficiário: | Leandro Martinez |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 13/08293-7 - CECC - Centro de Engenharia e Ciências Computacionais |
| Beneficiário: | Munir Salomao Skaf |
| Modalidade de apoio: | Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs |
| Processo FAPESP: | 13/05475-7 - Métodos computacionais de otimização |
| Beneficiário: | Sandra Augusta Santos |
| Modalidade de apoio: | Auxílio à Pesquisa - Temático |