This paper describes two computer programs designed to assist in the comparison of protein structures. LOPAL (LOoP ALignment) applies a dynamic programming algorithm to the comparison of regions of protein three-dimensional (3D) structure and gives a similarity score and suggested sequence alignment with that score. SCAMP (Structure Comparison and Alignment of Multiple Proteins) is an interactive graphics program for the Evans and Sutherland PS300 graphics terminal that allows the simultaneous display, manipulation and pairwise least-squares fitting of up to nine independent structures. Together, LOPAL and SCAMP provide an integrated system for characterizing structural similarities in proteins with the aim of improving the accuracy of predicted protein structures. An application of these programs to loop regions in the immunoglobulin constant domains is illustrated.
- automatic structure comparison
- dynamic programming
- least-squares fitting
- protein structure
- PS300 graphics program