Solution structure and dynamics of Xanthomonas albilineans Cas2 provide mechanistic insight on nuclease activity.
FEBS Lett
; 592(1): 147-155, 2018 01.
Article
em En
| MEDLINE
| ID: mdl-29265362
ABSTRACT
Cas2 protein in the CRISPR-Cas system functions as a scaffold for the acquisition of foreign DNA fragments, and as a nuclease against DNA and RNA substrates. Crystal structures of Cas2 have shown catalytically inactive conformational states that do not explain the mechanism of Cas2 nuclease activity. Here, we report that Xanthomonas albilineans Cas2 (XaCas2) assumes an inactive conformation in solution. Residual dipolar couplings and NMR relaxation, however, provide direct evidence on conformational dynamics at the predicted hinge region. Furthermore, XaCas2 transiently associates with metal ions for nuclease activity via highly mobile Asp8. Taken together, the dual function of Cas2 can be explained by a dynamic equilibrium of conformational states that serve as a scaffold or as a nuclease on demand.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
Xanthomonas
Tipo de estudo:
Prognostic_studies
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article