Chemical Shift Perturbation Mapping Slow or fast exchange A=X6NHP+(615N2 x=4,10....or some other number Mott et al (2003)J.Biol Chem.27817053-17 Binding a(larger)protein ligand to a labelled protein gCD2(10 kDa)titrated with CD48(540 kDa-glycosylated A 1:0 B 1:02 11 s52 0s52 S52 0 . o. 117- 90 o moar ratio of D4 McAlister et al(1996)Biochemistry 355982-5991 1:0 1:0.5 1:1.0 Chemical Shift Perturbation Mapping Slow or fast exchange # = [x($NH)2 + ($15N)2] 1/2 x = 4, 10 ….or some other number 40 50 60 70 80 90 100 0 1 2 3 4 5 0 10 20 30 Mott et al (2003) J. Biol Chem. 278 17053-17059 Binding a (larger) protein ligand to a labelled protein Overall broadening due to increase in %c. Selective broadening of some residues e.g. CD2 (10 kDa) titrated with CD48 (~35-40 kDa - glycosylated) McAlister et al (1996) Biochemistry 35 5982-5991 Fractional reduction in peak height #h = (hi -hx)/(hi -hf ) plotted against molar ratio of CD48 1:0 1:0.2 1:1