The program just requires the sequence and lets you define loops and other features. The program can also be used for energy minimization, to fit residues into electron density maps, determination of crystal symmetries, superposing proteins, analyzing active sites and much more. This name of this program is definitely a Swiss understatement. This site shows fascinating rotating pictures of DNA, proteins, and antibodies. RasMol is free software for looking at chemical structures.
Chime shows molecules inside a Web page.
This RasMol home page, which is maintained by Eric Martz of the Department of Microbiology at the University of Massachusetts, has been visited by 250,000 people from 115 countries. It is an absolute must see site. A cooperative presentation of the European and American Societies for Photobiology. An online primer for people who wish to learn more about photobiology, it is also a great resource for researchers in photochemistry and photobiology. Photobiology is the branch of biology that looks at the interaction of light and living organisms.