Escherichia coli YcaQ is a DNA glycosylase that unhooks DNA interstrand crosslinks.
Nucleic Acids Res
; 48(13): 7005-7017, 2020 07 27.
Article
em En
| MEDLINE
| ID: mdl-32409837
ABSTRACT
Interstrand DNA crosslinks (ICLs) are a toxic form of DNA damage that block DNA replication and transcription by tethering the opposing strands of DNA. ICL repair requires unhooking of the tethered strands by either nuclease incision of the DNA backbone or glycosylase cleavage of the crosslinked nucleotide. In bacteria, glycosylase-mediated ICL unhooking was described in Streptomyces as a means of self-resistance to the genotoxic natural product azinomycin B. The mechanistic details and general utility of glycosylase-mediated ICL repair in other bacteria are unknown. Here, we identify the uncharacterized Escherichia coli protein YcaQ as an ICL repair glycosylase that protects cells against the toxicity of crosslinking agents. YcaQ unhooks both sides of symmetric and asymmetric ICLs in vitro, and loss or overexpression of ycaQ sensitizes E. coli to the nitrogen mustard mechlorethamine. Comparison of YcaQ and UvrA-mediated ICL resistance mechanisms establishes base excision as an alternate ICL repair pathway in bacteria.
Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
3_ND
Base de dados:
MEDLINE
Assunto principal:
Dano ao DNA
/
DNA Glicosilases
/
Reparo do DNA
/
Escherichia coli
Idioma:
En
Revista:
Nucleic Acids Res
Ano de publicação:
2020
Tipo de documento:
Article