Partial characterization of goat brain proteins involved in bilirubin binding

In order to characterize in terms of bilirubin binding, major proteins in t he goat brain were separated into five different peaks, namely P-0, P-1, P- 2, P-3 and P-4 on a Seralose-6B column (90.5 x 2.5 cm), The peak P-0 was el uted with the void volume of the column, The molecular weights and Stokes r adii of the remaining peak proteins were: P-1 (1,06,727 and 4.11 nm), P-2 ( 59,256 and 3.25 nm), P-3 (18,713 and 1.71 nm) and P-4 (11,928 and 1.14 nm). Bilirubin binding studies indicated that three out of the five peak protei ns, namely P-1, P-2, and P-3 showed bilirubin binding as characterized by t he blue shift and hyperchromism in the visible absorption spectra and quenc hing of the protein fluorescence upon addition of bilirubin to protein fluo rescence these peak proteins.