STUDIES ON THE CRYSTAL-STRUCTURE OF [L-MET](B0) BOVINE INSULIN AT 3.0-ANGSTROM RESOLUTION

Based on the crystal symmetry of [L-Met]B0 bovine insulin (LMBBI) and the fundamental theory of the molecular packing method, the scheme for the determination of the position and orientation of the molecules by only using one-dimensional rotation and one-dimensional translation w as chosen to be used, and therefore the calculation of the rotation fu nction of the molecular replacement method and the refinement of the r otational and translational parameters by using the R-factor search me thod were simplified greatly. After the preliminary refinement by usin g the macromolecular rigid body refinement technique, the molecular mo del was further refined and adjusted by using the energy-minimizing st ereochemical-restrained least squares refinement technique assisted by the manual revision on the difference Fourier maps. The L-Met residue s on the N-terminus of the B-chain appeared clearly on the final elect ron density map.