Structural and Functional Insights into the Evolution and Stress Adaptation of Type II Chaperonins.
Structure
; 24(3): 364-74, 2016 Mar 01.
Article
em En
| MEDLINE
| ID: mdl-26853941
ABSTRACT
Chaperonins are essential biological complexes assisting protein folding in all kingdoms of life. Whereas homooligomeric bacterial GroEL binds hydrophobic substrates non-specifically, the heterooligomeric eukaryotic CCT binds specifically to distinct classes of substrates. Sulfolobales, which survive in a wide range of temperatures, have evolved three different chaperonin subunits (α, ß, γ) that form three distinct complexes tailored for different substrate classes at cold, normal, and elevated temperatures. The larger octadecameric ß complexes cater for substrates under heat stress, whereas smaller hexadecameric αß complexes prevail under normal conditions. The cold-shock complex contains all three subunits, consistent with greater substrate specificity. Structural analysis using crystallography and electron microscopy reveals the geometry of these complexes and shows a novel arrangement of the α and ß subunits in the hexadecamer enabling incorporation of the γ subunit.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas Arqueais
/
Sulfolobus solfataricus
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Chaperoninas do Grupo II
Idioma:
En
Revista:
Structure
Assunto da revista:
BIOLOGIA MOLECULAR
/
BIOQUIMICA
/
BIOTECNOLOGIA
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
Austrália