Extended Data Fig. 3: Representative densities.

a, b, EM density segments for α.A (a) and β (b) subunits, respectively. The model is shown in carton representation. The density is shown in surface representation. c, d, Representative densities for light (c) and heavy chain (d) of 3D1 Fab. Regions are numbered. e, f, Representative densities for glycosylation on α.A (e) and β (f) subunits. g–i, Representative densities of the binding pockets formed by β(+)/α.A(−) (g), α.D(+)/β(−) (h) and α.B(+)/α.C(−) (i), respectively. The related key amino acids are labeled. j, k, Representative densities for transmembrane helices including M1, M2, M3 and M4 from β (j) and α.A (k), respectively. All of the isolated densities are contoured at 8σ.