1) The high resolution structure of J539 has been refined. All the amino acid residues have been located with the exception of three that appear to be disordered. 2) The three-dimensional structure of two crystal forms of a complex between lysozyme and the Fab of a monoclonal antibody to lysozyme have been determined. The method used was molecular replacement in which the known structures of the Fab and of lysozyme were used as probes to determine their orientations and positions in the new crystal.
