Figure 2.

Active site of our computational model of the POLRMT complex. A, active site of the GTP-bound complex, with conserved catalytic residues, and residues and water molecules important in coordinating active site Mg²⁺ metal ions displayed in line representation and GTP in stick mode. Metal ion A is to the left of metal ion B, and both are shown as spheres. B, comparison between the active sites of the GTP-, ATP-, and CTP-bound POLRMT complexes averaged over simulation trajectories, shown in magenta, teal, and green, respectively. For each system, the NTP molecule is shown in stick mode, and α and β carbons of the catalytic residues Tyr⁹⁹⁹ and Asp¹¹⁵¹ are shown in line mode.