Summary: We describe an extension to the Homologous Structure Alignment Database (HOMSTRAD; Mizuguchi et al. , Protein Sci. , 7, 2469–2471, 1998a) to include homologous sequences derived from the protein families database Pfam (Bateman et al. , Nucleic Acids Res. , 28, 263–266, 2000). HOMSTRAD is integrated with the server FUGUE (Shi et al. , submitted, 2001) for recognition and alignment of homologues, benefitting from the combination of abundant sequence information and accurate structure-based alignments.

Availability: The HOMSTRAD database is available at: http://www-cryst.bioc.cam.ac.uk/homstrad/. Query sequences can be submitted to the homology recognition/alignment server FUGUE at: http://www-cryst.bioc.cam.ac.uk/fugue/.

Contact: homstrad@cryst.bioc.cam.ac.uk