Figure 4

Two views of a portion of the surface of the viral particle showing the exposure of threonine15 and the pattern of its display. Polypeptide chains are shown as ribbons. The position of threonine15 is indicated in red space-fill. Note that the structure shown here (downloadable as 1GAV.pdb from http://www.rcsb.org/pdb/, the protein data bank website) is actually that of GA, a close MS2 relative with a highly similar structure [18]