Ssa2 has higher luciferase refolding activity compared to Ssa4. (A) Luciferase was denatured at 45°, and refolded in the presence of Ssa2 or Ssa4 and Ydj1. As shown, fraction of luciferase that refolded was higher in the presence of A2 than A4. (B) The denatured luciferase (40 nM) was incubated in the presence of 0.3 μM Ydj1, 0.5 μM Hsp70 (Ssa2 or Ssa4), 2.4 μM Sti1, and 0.9 μM Hsp82, and the refolding was monitored by measuring the increase in luminescence. The luciferase refolding curves for Ydj1:Ssa2, Ydj1:Ssa4, and Ydj1 alone in (B) are adapted from (A) for comparison. The labels are represented as the same order of magnitude of curve. Error bars represent SD from three different biological replicates.