The Bridge Helix of RNA Polymerase Acts as a Central Nanomechanical Switchboard for Coordinating Catalysis and Substrate Movement
Figure 2
The Link domain. (a) Arrangement of the Bridge Helix and Link domain relative to the nucleotide insertion site. The Link domain (purple) and Bridge Helix domain (green) are shown as cartoon structures using the same coloring scheme as in Figure 1(b). The nucleic acid substrates are depicted in space-filling mode. Note the contacts made by the rNTP γ-phosphate (phosphate atoms in orange and oxygen atoms in red) with scRPB2 R766 (shown in space-filling mode, light blue). (b) Alignment of Link domain sequences from the same species shown in Figure 1(c). The invariant arginine (R) is highlighted with a light green bar.
