title: Double-headed protease inhibitors from black-eyed peas. V. Analysis of the energetics of protease-inhibitor interactions.
abstract: The half-site reactivity of trypsin and chymotrypsin binding to two double-headed black-eyed pea protease inhibitors a trypsin-chymotrypsin inhibitor (BEPCI) had a trypsin inhibitor (BEPTI), is explained in terms of the energetics of these inhibitor-protease interactions. Free energy diagrams are constructed to facilitate interpretation of the energetics. Coupling-free energies are calculated to reflect the magnitude of the interdependence of protease-binding (alloassociation) and inhibitor subunit interactions (isoassociation). The experiment observation of the predominance of liganded monomer complexes for the lima bean inhibitor and the Bowman-Birk soybean inhibitor and the predominance of half-site-liganded complexes for BEPCI and BEPTI is the direct result of the magnitudes and signs of the coupling free energies which result from these protease-inhibitor interactions.
mesh_terms: D001665:Binding Sites; D002918:Chymotrypsin / Q000037:antagonists & inhibitors; D046911:Macromolecular Substances; D010940:Plant Proteins / Q000378:metabolism*; D011480:Protease Inhibitors; D011485:Protein Binding; D012639:Seeds / Q000378:metabolism*; D013816:Thermodynamics; D014361:Trypsin Inhibitors
chemical_list: D046911:Macromolecular Substances; D010940:Plant Proteins; D011480:Protease Inhibitors; D014361:Trypsin Inhibitors; D002918:Chymotrypsin