Fig. 2. Representative saturation transfer difference (  A ) and one-dimensional nuclear magnetic resonance (  B ) spectra recorded for a solution containing 1 mm suramin (S), 1 mm halothane (H), 10 mm hexanol (Hx), and the α isoform-3 G-protein subunit (Gα^i-3). Gα^i-3was expressed in and purified from  Spodoptera frugiperda insect cells. The region of the saturation transfer difference spectra where deuterated water (HOD) absorbs (approximately 4.8 ppm) was deleted from the figure for clarity of presentation.