Extended Data Fig. 1: Plasmid DNA digestion by PsCap5 in the presence of cyclic nucleotides and structures of the activated ligand-bound PsCap5 tetramers.
From: Activation of CBASS Cap5 endonuclease immune effector by cyclic nucleotides
a, Plasmid DNA digestion assay with di-, tri- and tetra- cyclic nucleotides with 3′3′, 2′3′ and 2′2′ linkages. Related to Fig. 1b that shows DNA digestion with only purine dinucleotide ligands. Plasmid digestion is observed only with 3′2′-cGAMP (3′2′GA) and 3′2′-c-diAMP (3′2′AA). Concentrations of PsCap5 and the ligands are 500 nM. The DNA cleavage products are analyzed by agarose gel electrophoresis followed by staining with ethidium bromide. The black and white colors are inverted for clarity. Plasmid DNA includes closed and open circle species. Each gel is a representative of at least three independent experiments. b, The 3′2′-c-diAMP liganded structure in C2 space group with a = 145.19 Å, b = 80.52 Å, c = 406.84 Å, α = γ = 90.0° and β = 90.6° unit cell is refined to 1.79 Å resolution and has three tetramer assemblies in the asymmetric unit (AU). c, The 3′2′-cGAMP containing structure in P21 space group and with a = 67.97 Å, b = 295.68 Å, c = 84.05 Å, α = γ = 90.0° and β = 113.8° unit cell is refined to 1.87 Å resolution and has two tetramer complexes in the AU. d, The 3′2′-c-diAMP liganded structure in P322 space group with the a = b = 83.54 Å, c = 401.96 Å, α = β = 90.0° and γ = 120° unit cell is refined to 2.11 Å and has a single tetramer assembly in the AU.
