Fig 3. BsSufU alters the H/D exchange of BsSufS upon binding.

Changes in relative fractional deuterium uptake of BsSufS after incubation with BsSufU for 15 s in D₂O buffer compared to BsSufS alone were mapped onto the surface of the BsSufS (A) monomer and (B) homodimer. A decrease (blue) in deuterium uptake signals protection (i.e., a binding event), whereas an increase (red) signals a structural rearrangement. Black regions were not detected. Binding of BsSufU to (C) the C-terminus and (D) the α-hinge of BsSufS as a function of deuterium uptake over time. Color code: BsSufS alone (green), BsSufS + BsSufU (red), BsSufS + BsFra (blue), and BsSufS + BsSufU/BsFra (violet). N-terminus (NT) and C-terminus (CT).