Display, manipulation, and simulation of macromolecules

A set of building and displaying programs has been written and applied to serve as tools in the study of the interaction of proteins with DNA and RNA. This study, which has involved the use of a variety of computers, is a collaborative project between the group at RPMI, Buffalo, New York, and NASA‐Ames, California. The RPMI system, which is currently running on the Univac 70 computer, is easily adaptable to any computer, with or without sophisticated graphics hardware. Hence we emphasize the availability of an easy to handle and inexpensive means for building, displaying, and manipulating molecules. The RPMI system also includes an automated, nonin–teractive program for fast construction of specified molecular structures. The NASA system is running on an Evans and Sutherland display system which has sophisticated hardware and which is capable of continuously rotating the molecule with constant adjustment of perspective and intensity.