The RCSB Protein Data Bank (PDB) - Archive of experimentally-determined, biological macromolecule 3-D structures from the Brookhaven National Laboratory. Also includes newsletters and a description of the PDB file format. Nucleic Acid Database (NDB) - assembles and distributes structural information about nucleic acids. Peptaibol Database - Aims to provide a fully searchable database for the sequences of peptaibols. It deals primarily with naturally-occurring peptides, generally these have a fungal origin. SDPD-Database - Structure Determination by Powder Diffraction - Database : methods, tutorials, references and links. Powder Diffraction File (PDF) - maintained by the International Centre for Diffraction Data (ICDD) Heavy Atom Databank (HAD) - Information on the preparation and characterisation of heavy-atom derivatives of protein crystals. Also contains information resulting from an analysis of the binding of these heavy-atoms with proteins in the crystal environment. CSDSymmetry - The most complete collation of observed molecular and crystallographic symmetry properties to date. A relational database built using Microsoft Access. Crystal TB - A database containing information on Protein Crystallization Conditions. It helps researchers in setting conditions for protein crystallization, thus contributing to reducing the time to analyze protein structures. Cambridge Structural Database (CSD) - Contains crystal structure information, chemical, and bibliographic data for about 400,000 organic and metal-organic compounds. Biological Macromolecule Crystallization Database (BMCD) - Contains crystal data and the crystallization conditions, which have been compiled from literature, including proteins, protein:protein complexes, nucleic acid, nucleic acid:nucleic acid complexes, protein:nucleic acid complexes, and viruses. Inorganic Crystal Structure Database (ICSD) - Contains records of all inorganic crystal structures, with atomic coordinates.