BioCyc:RXN-21266

Excision of the nucleobase lesion is a two-step process and involves formation of an enzyme-substrate Schiff base intermediate; subsequent DNA strand nicking occurs via a β,δ-elimination leaving a 3'-terminal phosphate and a 5'-terminal phosphate. This reaction is catalysed by the Fpg (MutM) family of bifunctional DNA glycosylases.

a-purine-base-lesion-in-DNA + WATER --> 3-Prime-Phosphate-Terminated-DNAs + 5-Phospho-terminated-DNAs + CPD-21221 + Modified-Bases

[] + H2O[H2O] = 3'-end 5'-phosphate-ribonucleotide(3-) residue[C5H7O8P2R] + 5'-end 2'-deoxyribonucleotide(2-) residue[C5H7O6PR] + Pent-2-ene-1,4-dione[C5H6O2] + a modified nucleobase[]

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Alias

Metabolites

Substrates
metabolite compartment Structure


Formula: 		Cytoplasm
H2O

Formula: H2O 		Cytoplasm
Products
metabolite compartment Structure
3'-end 5'-phosphate-ribonucleotide(3-) residue

Formula: C5H7O8P2R		 Cytoplasm
5'-end 2'-deoxyribonucleotide(2-) residue

Formula: C5H7O6PR		 Cytoplasm
Pent-2-ene-1,4-dione

Formula: C5H6O2		 Cytoplasm
a modified nucleobase

Formula: 		Cytoplasm