Identification of cooperative folding units in a set of native proteins.
Protein Sci
; 6(8): 1627-42, 1997 Aug.
Article
en En
| MEDLINE
| ID: mdl-9260276
ABSTRACT
Cooperative unfolding penalties are calculated by statistically evaluating an ensemble of denatured states derived from native structures. The ensemble of denatured states is determined by dividing the native protein into short contiguous segments and defining all possible combinations of native, i.e., interacting, and non-native, i.e., non-interacting, segments. We use a novel knowledge-based scoring function, derived from a set of non-homologous proteins in the Protein Data Bank, to describe the interactions among residues. This procedure is used for the structural identification of cooperative folding cores for four globular proteins bovine pancreatic trypsin inhibitor, horse heart cytochrome c, French bean plastocyanin, and staphylococcal nuclease. The theoretical folding units are shown to correspond to regions that exhibit enhanced stability against denaturation as determined from experimental hydrogen exchange protection factors. Using a sequence similarity score for related sequences, we show that, in addition to residues necessary for enzymatic function, those amino acids comprising structurally important folding cores are also preferentially conserved during evolution. This implies that the identified folding cores may be part of an array of fundamental structural folding units.
Texto completo:
1
Base de datos:
MEDLINE
Asunto principal:
Plastocianina
/
Aprotinina
/
Pliegue de Proteína
/
Grupo Citocromo c
/
Nucleasa Microcócica
Tipo de estudio:
Diagnostic_studies
/
Prognostic_studies
Límite:
Animals
Idioma:
En
Revista:
Protein Sci
Asunto de la revista:
BIOQUIMICA
Año:
1997
Tipo del documento:
Article
País de afiliación:
Estados Unidos