Dictionary of Protein Sites and Patterns
Release 2021_03, Jun 21
Swiss Institute of Bioinformatics
2,632 entries

Protein families database of alignments and HMMs
Release 35.0, Nov 21
The Pfam Consortium
19,482 entries

NCBI Conserved Domain Database
Release 3.19, Feb 21
National Center for Biotechnology Information
58,235 entries