RCSB PDB (Research Collaboratory for Structural Bioinformatics PDB) operates the US data center for the global PDB archive, and makes PDB data available at no charge to all data consumers without limitations on usage.
The Protein Data Bank (PDB) was established as the 1st open access digital data resource in all of biology and medicine. It is today a leading global resource for experimental data central to scientific discovery.
The database is very actively maintained and is user friendly. Search for proteins from a variety of organisms and collect structure data for proteins of interest. Each protein has a variety of annotation that are neatly laid out for the user to comb through.