PRINTS–a protein motif fingerprint database

The PRINTS database of protein 'fingerprints' is described. Fingerprints comprise sets of motifs excised from conserved regions of sequence alignments, their diagnostic power or potency being refined by iterative database scanning (in this case the OWL composite sequence database). Generally, the motifs do not overlap, but are separated along a sequence, though they may be contiguous in 3-D space. The use of groups of independent, linearly or spatially separate motifs allows particular protein folds and functionalities to be characterized more flexibly and powerfully than conventional single-component patterns or regular expressions. The current version of the database (4.0) contains 150 entries (encoding > 700 motifs), covering a wide range of globular and membrane proteins, modular polypeptides and so on. The growth of the database is influenced by a number of factors, e.g. the use of multiple motifs, the maximization of sequence information through iterative database scanning and the fact that the database searched is a large composite. The information contained within PRINTS is distinct from but complementary to the single consensus expressions stored in the widely used PROSITE dictionary of patterns.