The conformational changes coupling ATP hydrolysis and translocation in a bacterial DnaB helicase.
Nat Commun
; 10(1): 31, 2019 01 03.
Article
em En
| MEDLINE
| ID: mdl-30604765
ABSTRACT
DnaB helicases are motor proteins that couple ATP-hydrolysis to the loading of the protein onto DNA at the replication fork and to translocation along DNA to separate double-stranded DNA into single strands during replication. Using a network of conformational states, arrested by nucleotide mimics, we herein characterize the reaction coordinates for ATP hydrolysis, DNA loading and DNA translocation using solid-state NMR spectroscopy. AMP-PCP is used as pre-hydrolytic, ADPAlF4- as transition state, and ADP as post-hydrolytic ATP mimic. 31P and 13C NMR spectra reveal conformational and dynamic responses to ATP hydrolysis and the resulting DNA loading and translocation with single amino-acid resolution. This allows us to identify residues guiding the DNA translocation process and to explain the high binding affinities for DNA observed for ADPAlF4-, which turns out to be optimally preconfigured to bind DNA.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Bactérias
/
DNA de Cadeia Simples
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Trifosfato de Adenosina
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DnaB Helicases
Idioma:
En
Revista:
Nat Commun
Ano de publicação:
2019
Tipo de documento:
Article