ITC trace for ColN2-185 binding to detergent solubilized BE3000 outer membranes (OmpF+) (filled square). From two repeats, an average Kd of 119 nm, ΔH of −38.8 kcal/mol, ΔS of −98.1 cal/mol/K were determined. The “OmpF−” trace represents ColN2-185 binding to detergent-solubilized BZB1107 outer membranes. All ITC experiments were conducted in 20 mm potassium phosphate, pH 6.5, 1% β-OG. Either solubilized BE3000 or BZB1107 was present in the cell, the syringe injected 100 μm ColN2-185.