Fpg (also known as Formamidopyrimidine DNA glycosylase, Mut M, FAPY DNA Glycosylase, and 8-oxoguanine DNA glycosylase) participates in the base-excision (BER) pathway of DNA repair enzymes and acts both as a N-glycosylase and an AP-lyase. The N-glycosylase activity releases damaged purines from double stranded DNA, generating an apurinic/apyrimidinic (AP site). The AP-lyase activity cleaves both the 3" and 5" phosphodiester bonds at the AP site, producing a 1 base gap in the DNA and 3" and 5" phosphate termini. Bases recognized and removed by Fpg include 7, 8-dihydro-8-oxoguanine (8-oxoguanine), 8-oxoadenine, fapy- guanine, methy-fapy-guanine, fapy-adenine, aflatoxin B1- fapy-guanine, 5-hydroxy-cytosine and 5-hydroxy-uracil.
A recombinant E. coli strain carrying the cloned fpg gene.
One unit is defined as the amount of enzyme required to cleave 1 pmol of a 34mer oligo-nucleotide duplex containing an 8-oxoguanine base in 1 hour at 37 °C in 1X Yellow Reaction Buffer.
100 mM BisTris-Propane-HCl100 mM MgCl210 mM DTTpH 7.0 @ 25 °C
20 mM Tris-HCl50 mM NaCl1.0 mM DTT0.1 mM EDTA 50% glycerolpH 8.0 at 25 °C