DNA damage-signaling, homologous recombination and genetic mutation induced by 5-azacytidine and DNA-protein crosslinks in Escherichia coli.

ABSTRACT: Covalent linkage between DNA and proteins produces highly toxic lesions and can be caused by commonly used chemotherapeutic agents, by internal and external chemicals and by radiation. In this study, using Escherichia coli, we investigate the consequences of 5-azacytidine (5-azaC), which traps covalent complexes between itself and the Dcm cytosine methyltransferase protein. DNA protein crosslink-dependent effects can be ascertained by effects that arise in wild-type but not in dcmΔ strains. We find that 5-azaC induces the bacterial DNA damage response and stimulates homologous recombination, a component of which is Dcm-dependent. Template-switching at an imperfect inverted repeat ("quasipalindrome", QP) is strongly enhanced by 5-azaC and this enhancement was entirely Dcm-dependent and inde

SUBMITTER: Klaric JA 

PROVIDER: S-EPMC8288033 | biostudies-literature | 2021 Jan-Jun

REPOSITORIES: biostudies-literature