Figure 1.

Inhibitor nomenclature and structure/composition of libraries of P1 asparginyl peptide vinyl sulfones. (A) P notation used to define positions of interaction between inhibitor/substrate and enzyme active site. Sites labeled with S designate binding pockets of the enzyme. (B) Diagram of P2 and P3 positional scanning libraries and the P4 single component library. Constant positions made up of all possible natural amino acids (minus cysteine and using norleucine instead of methionine) are indicated by C_1–19. Variable positions that contain an isokinetic mixture of amino acids (the same 19 amino acids as constant positions) are indicated as Mix. Note that the P2 and P3 scanning libraries are composed of 19 sublibraries each containing a mixture of 19 members (one Mix position) whereas the P4 library is made up of 19 single compounds (no Mix position).