SAXS analysis of apo- and holo-SaBPL, SaBPL/DNA, and SaBPL/BCCP. (A) Scattering data for the six SaBPL, Sa-bioO, and SaBCCP samples (black crosses) with the predicted scattering curves (gray solid line) derived from models of these molecules and complexes (a.u. corresponds to arbitrary units). (B) Pair-wise distribution (P(r)) profiles for holo-SaBPL, Sa-bioO, and SaBPL/Sa-bioO complexes. (C) Ab initio reconstruction of the six samples overlaid with models derived from crystallographic structural data and modeling. (D) Pair-wise distribution (P(r)) profiles for apo-SaBPL, SaBCCP, and the SaBCCP/SaBPL complex. Note that each of the six scattering curves, P(r) profiles, and ab initio models are correlated by a Roman numeral label.