Protein Validation servers and freeware

Procheck
Check the stereochemical quality of a protein structure

Biotech
Validation suite for protein structures

Pages with links to many programs

Links for Protein Crystallography, Sequence Analysis and Mathematics
From the Structural Medicine group at the University of Cambridge

Computational Services at EMBL
Sequence search & retrieval, sequence alignment, sequence databases, structure comparison, structure prediction, structure verification, and others

ExPASy Molecular Biology Server
Databases, tools and software packages, education and services and links

Bioinformatic Resources at the BCSB

The 3D Protein Structure Lab
The Richardson's protein freeware at Duke

The Brutlag Bioinformatics Group