Figure S4 - DNA competition assays with alternate hairpin DNAs measured by fluorescence anisotropy. 5'-labeled template DNA was excited at 550 nm with emission signal collected at 580 nm. 100 nM primer-template DNA was pre-bound to 1 uM wild-type clamp loader in the presence of 1 uM wild-type beta clamp and 1 mM ADP-BeFx (1 mM ADP, 2 mM BeCl, 10 mM NaF). Hairpin DNAs used here were of the sequence 5'-CGTAACTAGTTAACTAGTACGACCCCCTCGTACTAGTTAACTAGTTACG-3' having 5' or 3' overhangs composed of additional thymine residues at the appropriate ends.