FIG. 9.

Effect of GlnB on deuridylylation. Reaction mixtures contained 1.3 μM GlnD, 3 mM MnCl₂, 500 μM α-ketoglutarate, 2 mM ATP, 10 mM glutamine, and 0.5 mM UTP supplemented with [α-³²P]UTP. Lanes 1 and 2 also contained 0.4 μM GlnB and 0.4 μM His-GlnB-UMP, while only His-GlnB-UMP was added in lanes 3 and 4. Samples were withdrawn from the reaction mixtures after 5 min (lanes 1 and 3) or after 60 min (lanes 2 and 4). Note that both experiments were performed under deuridylylation conditions (1.3 μM GlnD and 10 mM glutamine) but with 0.5 mM UTP supplemented with [α-³²P]UTP also included in the assay. Samples were subjected to SDS-PAGE and visualized by autoradiography.