Fig. 4From: Possibility for detecting 14 typical odorants occurring in drinking water by employing human odor-binding protein OBP2aThree-dimensional structure of OBP2a (a) and analysis of binding mechanisms of OBP2a to 2-ethyl-4-methyl-1,3-dioxolane (b), 2-octenal (c), and 2-isobutyl-3-methoxy pyrazine (d). Purple arrow, hydrogen bonding; green arrow, pi–pi stackingBack to article page