Classification and use of macromolecular data

Abstract

The macromolecular CIF (mmCIF) dictionary is a major extension of the core CIF dictionary designed to provide data names to be used in a machine-readable description of a macromolecular structure determination experiment and the derived structural model. To allow a complete and self-consistent account of a macromolecular structure at various levels of detail, the dictionary has been implemented in the relational dictionary definition language DDL2. It includes the data items defined in the core CIF dictionary. mmCIF supersedes an older file format of the Protein Data Bank (PDB), and therefore includes a representation of all the information historically archived at the PDB. In addition, it provides data items suitable for use in: a journal `materials and methods' article; descriptions of biologically active molecules and any important subcomponents; descriptions of crystallographic and noncrystallographic symmetry; information about the chemistry and geometry of monomer components of macromolecules, and of any ligands or small-molecule complexes; and descriptions of functional and structural aspects of macromolecules. This chapter is also available as HTML from the International Tables Online site hosted by the IUCr.