Abstract
The SWISS-2DPAGE database (http: //www.expasy.ch/ch2d/ch2d-top.html ) consists of two-dimensional polyacrylamide gel electrophoresis images, as well as textual descriptions of the proteins that have been identified on them. The current release contains 15 reference maps from human biological samples, as well as from Saccharomyces cerevisiae , Escherichia coli and Dictyostelium discoideum origin. These reference maps have 2088 identified spots, corresponding to 410 separate protein entries in the database, in addition to virtual entries for each SWISS-PROT sequence.