Events associated with DNA replication disruption are not observed in hydrogen peroxide-treated Escherichia coli.
G3 (Bethesda)
; 11(4)2021 04 15.
Article
en En
| MEDLINE
| ID: mdl-33591320
ABSTRACT
UV irradiation induces pyrimidine dimers that block polymerases and disrupt the replisome. Restoring replication depends on the recF pathway proteins which process and maintain the replication fork DNA to allow the lesion to be repaired before replication resumes. Oxidative DNA lesions, such as those induced by hydrogen peroxide (H2O2), are often thought to require similar processing events, yet far less is known about how cells process oxidative damage during replication. Here we show that replication is not disrupted by H2O2-induced DNA damage in vivo. Following an initial inhibition, replication resumes in the absence of either lesion removal or RecF-processing. Restoring DNA synthesis depends on the presence of manganese in the medium, which we show is required for replication, but not repair to occur. The results demonstrate that replication is enzymatically inactivated, rather than physically disrupted by H2O2-induced DNA damage; indicate that inactivation is likely caused by oxidation of an iron-dependent replication or replication-associated protein that requires manganese to restore activity and synthesis; and address a long standing paradox as to why oxidative glycosylase mutants are defective in repair, yet not hypersensitive to H2O2. The oxygen-sensitive pausing may represent an adaptation that prevents replication from occurring under potentially lethal or mutagenic conditions.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Banco de datos:
MEDLINE
Asunto principal:
Proteínas de Escherichia coli
/
Escherichia coli
Tipo de estudio:
Risk_factors_studies
Idioma:
En
Revista:
G3 (Bethesda)
Año:
2021
Tipo del documento:
Article
País de afiliación:
Estados Unidos