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This picture identifies a generic drug-enzyme complex taken from an exam script. There is no name given. One part of the exam question states:
Propose a structure based pharmacophore for the family of drugs to which this one belongs.
I understand that a pharmacophore is the minimum structure required to exert a certain biological activity. Therefore, my answer would go something like the following:
We would need a drug with similar steric conformities to fill the entire active site (competitive inhibition) and that has some form of interaction at either end which keeps it in place, e.g., $\pi-\pi$ stacking with Phe groups or the H-bond and electrostatic interactions with Arg.
But would that paragraph above be a viable answer? Would this drug work just as well if it didn't have the $\pi-\pi$ stacking with the Phe groups, for instance? Are the interactions between the drug and the Lys and Glu residues dispensable - maybe that region of the drug is only there for its length?