Figure 3.

N protein binding and compaction at varying protein and salt concentrations. (A) Significant ssDNA compaction is observed for N protein concentrations as low as 1 nM. Low protein concentration requires a longer timescale to achieve full compaction and the two steps of compaction observed at high concentration are no longer individually resolvable. Right bar graph shows average extension change at the end of N protein incubation for each condition. (B) The degree of N protein-mediated ssDNA compaction is altered by the salt concentration of the experimental buffer, with very high NaCl concentrations inhibiting binding and compaction. Error bars represent standard error for N = 10 ([NaCl] = 150 mM, [N] = 100 nM) or N = 3 (all other conditions) experimental replicates.