Domain Database (CDD) is a collection of multiple sequence alignments that
represent functional domains conserved across evolution. Conserved Domains (CDs) are recurring polypeptide chains or modules which have
distinct evolutionary origin and function.
Modeling Database (MMDB) contains 3D macromolecular structures retrieved
from the Protein Data Bank
(PDB) database. MMDB contains over 28,000 structures which are determined
by experimental methods, primarily X-ray crystallography and Nuclear Magnetic
Resonance (NMR) spectroscopy. Theoretical models are not included.
Domains are annotations on individual Molecular
Modeling Database (MMDB) structures that define compact structural
domains contained within them.