Protein Stability in Titan's Subsurface Water Ocean.
Astrobiology
; 20(2): 190-198, 2020 02.
Article
em En
| MEDLINE
| ID: mdl-31730377
ABSTRACT
Models of Titan predict that there is a subsurface ocean of water and ammonia under a layer of ice. Such an ocean would be important in the search for extraterrestrial life since it provides a potentially habitable environment. To evaluate how Earth-based proteins would behave in Titan's subsurface ocean environment, we used molecular dynamics simulations to calculate the properties of proteins with the most common secondary structure types (alpha helix and beta sheet) in both Earth and Titan-like conditions. The Titan environment was simulated by using a temperature of 300 K, a pressure of 1000 bar, and a eutectic mixture of water and ammonia. We analyzed protein compactness, flexibility, and backbone dihedral distributions to identify differences between the two environments. Secondary structures in the Titan environment were found to be less long-lasting, less flexible, and had small differences in backbone dihedral preferences (e.g., in one instance a pi helix formed). These environment-driven differences could lead to changes in how these proteins interact with other biomolecules and therefore changes in how evolution would potentially shape proteins to function in subsurface ocean environments.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas
/
Estrutura Secundária de Proteína
/
Saturno
/
Exobiologia
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Astrobiology
Assunto da revista:
BIOLOGIA
Ano de publicação:
2020
Tipo de documento:
Article
País de publicação:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
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US
/
USA