Abstract:
DNA repair is essential to counteract damage to DNA induced by
endo- and exogenous factors, to maintain genome stability. However, challenges to
the faithful discrimination between damaged and non-damaged DNA strands do
exist, such as mismatched pairs between two regular bases resulting from
spontaneous deamination of 5-methylcytosine or DNA polymerase errors during
replication. To counteract these mutagenic threats to genome stability, cells evolved
the mismatch-specific DNA glycosylases that can recognize and remove regular
DNA bases in the mismatched DNA duplexes. The Escherichia coli adenine-DNA
glycosylase (MutY/MicA) protects cells against oxidative stress-induced mutagenesis
by removing adenine which is mispaired with 7,8-dihydro-8-oxoguanine (8oxoG)
in the base excision repair pathway....