The recombination initiation functions DprA and RecFOR suppress microindel mutations in Acinetobacter baylyi ADP1.
Mol Microbiol
; 122(1): 1-10, 2024 07.
Article
em En
| MEDLINE
| ID: mdl-38760330
ABSTRACT
Short-Patch Double Illegitimate Recombination (SPDIR) has been recently identified as a rare mutation mechanism. During SPDIR, ectopic DNA single-strands anneal with genomic DNA at microhomologies and get integrated during DNA replication, presumably acting as primers for Okazaki fragments. The resulting microindel mutations are highly variable in size and sequence. In the soil bacterium Acinetobacter baylyi, SPDIR is tightly controlled by genome maintenance functions including RecA. It is thought that RecA scavenges DNA single-strands and renders them unable to anneal. To further elucidate the role of RecA in this process, we investigate the roles of the upstream functions DprA, RecFOR, and RecBCD, all of which load DNA single-strands with RecA. Here we show that all three functions suppress SPDIR mutations in the wildtype to levels below the detection limit. While SPDIR mutations are slightly elevated in the absence of DprA, they are strongly increased in the absence of both DprA and RecA. This SPDIR-avoiding function of DprA is not related to its role in natural transformation. These results suggest a function for DprA in combination with RecA to avoid potentially harmful microindel mutations, and offer an explanation for the ubiquity of dprA in the genomes of naturally non-transformable bacteria.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Recombinases Rec A
/
Recombinação Genética
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Proteínas de Bactérias
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Acinetobacter
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Mutação
Idioma:
En
Revista:
Mol Microbiol
Assunto da revista:
BIOLOGIA MOLECULAR
/
MICROBIOLOGIA
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
Noruega