Table 2.

Comparative Properties of Mammalian DNA Glycosylases for Oxidized Bases

Properties	Nth Type		Nei Type
	OGG1	NTH1	NEIL1	NEIL2
Size (kD)	38	36	43	36
DNA structure	dsDNA	dsDNA	ssDNA; Bubble, Fork, and dsDNA	ssDNA; Bubble, Fork, and dsDNA
Downstream Enzyme	APE1	APE1	PNK	PNK
Conserved motif	HhH	HhH	H2TH	H2TH
Catalytic residue	Lys 249	Lys 212	Pro1	Pro1
Cell Cycle Dependence	None	None	S-phase Specific	None
Dispensable Sequences	C-terminal 20 & N-terminal 10 residues	N-terminal 80 residues	C-terminal 101 residues	C-terminal 10 residues
AP lyase	β-elimination (3′ PUA)		βδ-elimination (3′ phosphate)

ds, double stranded; ss, single-stranded; HhH, helix-hairpin-helix; H2TH, helix-2-turn-helix.