Abstract: Ricin A-chain is an N-glycosidase that attacks ribosomal RNA at a highly conserved adenine residue. Crystallographic studies show that not only adenine and formycin, but also pterin-based rings can bind in the ricin active site. For a better understanding of the recognition mode between ricin, and adenine-like rings, the interaction energies and geometries were calculated for a number of complexes. Shiga toxin, a compound essentially identical to the protein originally isolated from Shigella dysenteniae, has an active protein chain that is a homologue of the ricin active chain, and catalyzes the same depurination reaction. The present invention is drawn to identifying inhibitors of ricin and Shiga toxin, using methods molecular mechanics and ab initio methods and using the identified inhibitors as antidotes to ricin or Shiga toxin, or to facilitate immunotoxin treatment by controlling non-specific cytotoxicity.

Abstract: Ricin A-chain is an N-glycosidase that attacks ribosomal RNA at a highly conserved adenine residue. Crystallographic studies show that not only adenine and formycin, but also pterin-based rings can bind in the ricin active site. For a better understanding of the recognition mode between ricin, and adenine-like rings, the interaction energies and geometries were calculated for a number of complexes. Shiga toxin, a compound essentially identical to the protein originally isolated from Shigella dysenteriae, has an active protein chain that is a homologue of the ricin active chain, and catalyzes the same depurination reaction. The present invention is drawn to identifying inhibitors of ricin and Shiga toxin, using methods molecular mechanics and ab initio methods and using the identified inhibitors as antidotes to ricin or Shiga toxin, or to facilitate immunotoxin treatment by controlling non-specific cytotoxicity.

Abstract: The present invention relates to non-phosphorus containing O-malonyltryrosyl compounds, derivatives thereof, uses of the O-malonyltryrosyl compounds in the synthesis of peptides, and O-malonyltryrosyl compound-containing peptides. The O-malonyltyrosyl malonyltyrosyl compounds and O-malonyltryrosyl compound-containing peptides of the present invention are uniquely stable to phosphotases, capable of crossing cell membranes, suitable for application to peptide synthesis of O-malonyltryrosyl compound-containing peptides, and amenable to prodrag defivatization for delivery into cells. The present invention also provides for O-malonyltryrosyl compound-containing peptides which exhibit inhibitory potency against binding interactions of receptor domains with phosphotyrosyl-containing peptide ligands.