Can computational binding site similarity tools verify the hypothesis: “Biosynthetic moldings give potent biological activities to natural products”? To answer this question, we designed a tool modeling binding site properties according to solvent exposure. The method showed interesting characteristics but suffers from sensitivity to atomic coordinates. However, existing methods have delivered evidence that the hypothesis was valid for the flavonoid chemical class. In order to extend the study, we designed an automated pipeline capable of searching natural product biosynthetic enzyme structures embedding ligandable catalytic sites. We collected structures of 117 biosynthetic enzymes. Finally, according to structural investigations of biosynthetic enzymes, we characterized diverse substrate-enzyme binding-modes, suggesting that natural product biological imprints usually do not agree with the “key-lock” model.