(A) Transfer of AV-glycolipid by wt-GLTP or D48V-GLTP (2 μg) as a function of time. The increase in fluorescence emission at 415 nm (AV emission) occurs because of decreased Förster resonance energy transfer that occurs as AV-glycolipid is removed from donor vesicles containing 3-perylenoyl PC and is transported to POPC acceptor vesicles, as described in the Methods.
(B) Selectivity enhancement of D48V-GLTP for sulfatide compared to wt-GLTP. The ratio of the initial rates of sulfatide and GalCer transfer by D48V-GLTP is increased 50- to 70-fold compared to wt-GLTP. Determinations are shown for three different protein levels (1, 2, and 3 μg of protein).
(C) Structure of 3-O-Sulfo-D-galactosyl-β1-1′-N-[12-(9-anthryl)-11E-dodecenoyl]-D-erythro-sphingosine (AV-sulfatide). See also Figure S2.