Structure of the lysozyme from bacteriophage T4: An electron density map at 2.4 Å resolution

The three-dimensional structure of the lysozyme from bacteriophage T4 has been determined from a 2.4 Å resolution electron density map. The map, determined using isomorphous replacement and anomalous scattering differences from platinum and mercury-substituted crystals, reveals the approximate conformation of the molecule unambiguously. Details of the structure determination are presented and the conformation of the molecule is described in detail. The observed properties of those mutant lysozymes for which the changes in the amino acid sequence have been determined are discussed in the light of the three-dimensional structure. In most cases the behavior of the mutant lysozymes can be easily rationalized, but there are a few instances where this is not so.