FIGURE 2.

Candida Pra1 binds C4BP as shown by ITC. Plasma purified C4BP and recombinant Pra1 were prepared and dialyzed in the same buffer DPBS. C4BP (300 μl with a concentration of 15 μm, 2.6 mg) was loaded into the sample cell, and Pra1 (60 μl at 353 μm, 1.3 mg) was applied into the syringe. The interaction was assayed at 25 °C, with a reference power of 5 μcal/s under low feedback mode. A total of 17 sequential injections were performed; the first injection was 0.3 μl, and the following 16 injection were 2.4 μl. After the interaction, the data were analyzed by a MicroCal ITC200. After 17 injections, the reaction appeared close to saturation. However to confirm that the reaction had reached saturation, additional Pra1 was applied in the syringe, and five subsequent infections were performed (inset panels on the right). During each injection, the heat of release is stable, representing background signals based on the ligand-buffer interaction. These inset panels further show the saturation of Pra1-C4BP interaction.