Interacting protein components (enzymes bearing a dockerin and scaffoldin or cohesin) were mixed at a final concentration of 10 µM at room temperature in 20 mM Tris-maleate pH 6.0, 1 mM CaCl 2, and 4 µL were subjected to native PAGE (4–15% gradient) using a Phastsystem apparatus (GE Healthcare).
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