Figure 3.

JGT is unable to utilize UDP-6-N₃-glucose. Denaturing PAGE for monitoring the reaction mixtures of DNA substrates treated with (A) T4 βGT or (B) JGT and UDP-glucose or UDP-6-N₃-glucose (azido-UDP-glucose). The 15-nt-long ³²P labeled dsDNA substrate containing either a 5hmU or 5hmC were incubated with the indicated GT enzyme and nucleotide sugar as described in the “Materials and methods” section. The addition of a glucose moiety to the DNA substrate results in a visible shift on PAGE, with an even greater shift upon subsequent addition of biotin. No enzyme control indicates DNA substrate incubated without the addition of the corresponding GT enzyme. The band indicated with an asterisk is a 14-nt-long glucosylated degradation product.