The PROMISE (Prosthetic centres and metal ions in protein active sites) database aims to gather together comprehensive sequence, structural, functional and bibliographic information on proteins which possess prosthetic centres, with an emphasis on active site structure and function. The database is available on the World Wide Web at http://bioinf.leeds.ac.uk/promise/ BACKGROUND Of the more than 5000 proteins of known three-dimensional structure, at least half contain metal ions or other non-protein prostheticgroupsintheiractivesites;suchprostheticgroupsoften themselves containing metal ions. Nature has made abundant use of the wide range of chemical properties of the elements, exemplified conspicuously by the complex coordination states of the transition metals. The presence of metal ions and other prosthetic groups confers vitally important properties on the proteins concerned, while the protein environments of the groups modulate the chemistry of the ions in subtle ways. The ‘tuni...
Kirill Degtyarenko, A. C. North, D. N. Perkins, Jo