Lattice Interactions in Crystals of Soybean Trypsin Inhibitor (Kunitz) Produced by Inclusion of 1,5-Disulfonylnaphthalene

In the course of an earlier investigation into the crystallization of proteins based on the addition of intermolecular ligands, the Kunitz type trypsin inhibitor from soybean (SBTI) was crystallized as a complex with 1,5-disulfonylnaphthalene (ligand library 21D). The two molecules within the asymmetric unit of the monoclinic crystals are related by a near-exact NCS 2-fold axis and have essentially the same conformation as was found for them in...