Patent ID: 7144988

Claim:
A crystal having a space group R3 and a unit cell dimension of a=96.3 Å, b=96.3 Å, and c=75.3 Å of a protein-ligand complex comprising a modified IL-1 receptor type 1 (IL-1R1) and a ligand, wherein: a. the modified IL-1 receptor type 1 consists of the amino acid sequence as set forth in SEQ ID NO: 2; b. the ligand forms a complex with the modified IL-1 receptor type 1 by binding to the amino acid sequence as set forth in SEQ ID NO: 2 and has a molecular weight of less than about 1500 g/mol; and c. the crystal effectively diffracts X-rays for the determination of atomic coordinates of the protein-ligand complex to a better resolution than 3.5 Angstroms.