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FIGURE 23-14 Immunoglobulin structure. This model shows the three-dimensional structure of an immunoglobulin molecule complexed with hen egg-white lysozyme (a protein antigen) as determined by x-ray crystallography.
[Data from E. A. Padlan et al., 1989, Proc. Natl. Acad. Sci. USA 86:5938, PDB ID 1igt, 3hfm.]