Electron density, carbohydrate structure

Fig. 6. Structure of the Fc fragment of human IgG. ( ), Alpha carbon positions (o), approximate centres of carbohydrate hexose units. Coordinates were obtained from the Brookhaven Data Bank (after Dei-senhofer [23]). The pairing of Cn3 domains and the position of carbohydrate between C 2 domains is clearly seen in this view. The contact between carbohydrate chains is much more extensive in rabbit Fc. Note that the heavy chains are described only from residue 238 residues 225-238 do not show well-defined electron density.

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