FIG. 5.

The effect of glutamine on uridylylation. In panels A, B, and C, 3 mM MnCl₂, 2 mM ATP, 60 μM α-ketoglutarate, and 0.5 mM UTP supplemented with [α-³²P]UTP were included in the reaction mixture. (A) GlnB (0.5 μM) with 0.13 μM purified R. rubrum GlnD. (B) GlnB (15 μM) with 50 μg E. coli GlnD activity. (C) Fifteen micromolar GlnB with R. rubrum N+ extract (120 μg protein). Lane 1, no glutamine added; lane 2, 10 mM glutamine added. Samples were withdrawn after 0 or 20 min of incubation and stopped by addition of SDS cocktail.