Figure 4.

Three-dimensional structures of birch pollen Bet v 1 and homologous food allergens. Structures reveal a typical alpha/beta fold that is responsible for IgE cross-reactivity among related and unrelated species. Secondary structure elements (A) are displayed in green (α-helices), yellow (β-sheets), and grey (loops and turns). The distribution of hydrophilic (blue) and hydrophobic (red) amino acids over the molecular surface is depicted in B. All models were obtained from the Protein Structure Database http://www.pdb.org/pdb/home/home.do and visualized with chimera http://www.cgl.ucsf.edu/chimera/