Figure S3 CryoEM analysis of PaqCI DNA-bound enzyme, Panel a

Size exclusion chromatographic elution behavior of PaqCI enzyme in the presence of a stoichiometric excess of double strand DNA (see Figure 3a) indicates formation of a stable DNA-bound enzyme complex. The elution profiles for free protein, free DNA and a 1:1 stoichiometric mixture of protein + DNA are shown as bold colored lines; the elution of molecular weight standards are shown as a light dashed grey profile The expected peak elution volumes for an enzyme monomer (56 kD) or dimer (112 kD) are indicated with labeled arrows. In this experiment, the DNA (as well as the protein-DNA complex) elute at a significant early volume due to the length of the DNA duplex used in the experiments.