References:
1. "3D-Fun: predicting enzyme function from structure" von Grotthuss M, Plewczynski D, Vriend G, and Rychlewski L Nucleic Acids Res. 2008 Jul 1;36(Web Server issue):W303-7 [html] [pdf]
2. "PDB-UF: database of predicted enzymatic functions for unannotated protein structures from structural genomics" von Grotthuss M, Plewczynski D, Ginalski K, Rychlewski L, and Shakhnovich EI BMC Bioinformatics. 2006 Feb 6;7(1):53 [html] [pdf]