Fig. 2
From: Primer synthesis by a eukaryotic-like archaeal primase is independent of its Fe-S cluster
The nucleotide-binding site in PriX. a View of the PriSLX structure, highlighting the position of the two bound AMPCPP molecules. The primase structure is drawn as in Fig. 1a, the AMPCPP is shown in stick representation. b Close-up view of the NTP-binding site of PriX with bound AMPCPP. The side chains of the amino acids that form the NTP-binding site are shown. Polar contacts between side chains of NTP-binding residues and AMPCPP are drawn as dashed lines, together with their distances in Ångström. The top-right inset shows a superposition of the yeast (green; PDB ID 3LGB) and human (pink; PDB ID 3Q36) PriL-CTD structures. The side chain of arginine residues R355 (yeast) and R306 (human), that are essential for initiation of primer synthesis, are also shown. The AMPCPP molecule of superimposed PriX (protein not shown) is overlaid on the PriL-CTD structures, to highlight its proximity to R355 and R306
