Chemical screens against a reconstituted multiprotein complex: myricetin blocks DnaJ regulation of DnaK through an allosteric mechanism.
Chem Biol
; 18(2): 210-21, 2011 Feb 25.
Article
em En
| MEDLINE
| ID: mdl-21338918
ABSTRACT
DnaK is a molecular chaperone responsible for multiple aspects of bacterial proteostasis. The intrinsically slow ATPase activity of DnaK is stimulated by its co-chaperone, DnaJ, and these proteins often work in concert. To identify inhibitors we screened plant-derived extracts against a reconstituted mixture of DnaK and DnaJ. This approach resulted in the identification of flavonoids, including myricetin, which inhibited activity by up to 75%. Interestingly, myricetin prevented DnaJ-mediated stimulation of ATPase activity, with minimal impact on either DnaK's intrinsic turnover rate or its stimulation by another co-chaperone, GrpE. Using NMR, we found that myricetin binds DnaK at an unanticipated site between the IB and IIB subdomains and that it allosterically blocked binding of DnaK to DnaJ. Together, these results highlight a "gray box" screening approach, which might facilitate the identification of inhibitors of other protein-protein interactions.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Flavonoides
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Proteínas de Choque Térmico HSP70
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Proteínas de Escherichia coli
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Proteínas de Choque Térmico HSP40
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article