MODEL STRUCTURES AND ACTION OF INTERLEUKIN-1 AND ITS ANTAGONIST

A comparison has been made between the homology and hydrophobicity pro files of six interleukin amino acid sequences and that of the human in terleukin 1beta (IL-1beta) for which a crystal structure exists. The r esulting sequence alignment was used to build model structures for the sequences for three IL-1alpha, two IL-1beta and an interleukin recept or antagonist. Analysis of these structures demonstrates that the inte rleukin molecule has a strong electric dipole which is generated by th e topological position of the amino acids in the sequence. Electrostat ic surface calculations implicate a particular residues (Lys145) as be ing fundamental to interleukin activity and this supports site-directe d mutation evidence that this residue is required for activity.