The latest version of the Conserved Domain Database contains 3,272 new or updated NCBI-curated domains and now mirrors Pfam version 31 as well as models from NCBIfams, a collection of protein family hidden Markov models (HMMs) for improving bacterial genome annotation. A fine-grained classification of the major facilitator superfamily has also been added. You can find this updated content on the CDD FTP site.
Database statistics for CDD version 3.17:
57242 total models are indexed in Entrez
4332 multi-model superfamilies are indexed in Entrez
52910 models form the default “cdd” search database
16709 models from Pfam v31
4873 models from COG v1
1012 models from SMART v6.0
10,885 domains from NCBI Protein Clusters
4488 models from the TIGRFAM v15 database
14908 models curated by NCBI/CDD
35 models from NCBIfams
The Conserved Domain Database is a resource for the annotation of functional units in proteins. Its collection of domain models includes a set curated by NCBI, which utilizes 3D structure to provide insights into sequence/structure/function relationships.