N2,3-etheno-G (N2,3-εG)

FULL NAME: N2,3-ethenoguanine


DESCRIPTION:
1,N2-ethenoguanine (1,2-εG) and its isomer 3,N2-ethenoguanine (2,3-εG) are cyclic DNA adducts formed, as with eA, by reagents such as chloroacetylaldehyde or 4-hydroperoxy-2-nonenal. The AlkA protein can release 2,3-εG from DNA. The glycosidic bond of 2,3-eG is extremely labile, a property that has made assessment of biological significance of this modified base a difficult task. Nevertheless, Loeb and colleagues successfully determined the mutation frequency of the lesion to be 13% in E.coli, where it primarily induces G → A transitions.

DAMAGE TYPE: DNA adduct


DNA DAMAGE SOURCE(S) (MAIN):
lipid peroxidation (LPO)
vinyl chloride metabolites
chloroacetaldehyde (CAA)


DNA DAMAGE EFFECT(S) (MAIN):
G→A transition
mutagenesis
point mutation
substitution
transition


PATHWAYS:
base excision repair (BER)


DNA repair protein(s) related to damage:
AlkA


Last modification date: Oct. 12, 2011