Fig. 4.

Essential modules for 5mC glycosylase activity of DME. (A) From DMEΔN677, the IDR1 is removed and replaced with a short linker sequence (lnk), producing DMEΔN677ΔIDR1∷lnk. Structures of full-length DME, DMEΔN677, and DMEΔN677ΔIDR1∷lnk are aligned together to compare their relative sizes and positions of the three conserved domains. Sizes of the fragments are indicated to the right. (B) DMEΔN677ΔIDR1∷lnk excises 5mC from methylated DNA substrate similarly to DMEΔN677. No-enzyme control or catalytic mutant DMEΔN677(D1304N) does not display 5mC excision activity. Oligonucleotide substrate (S) and β- and δ-elimination products are shown to the right of the panel.