DSDBASE is a database on disulphide bonds in proteins that provides information on native disulphides and those which are stereochemically possible between pairs of residues in a protein.

One of the potential uses of such a disulphide database is to design site-directed mutants in order to enhance the thermal stability of the protein in question. Another important application is to employ this database for proposing 3D models of disulphide-rich polypeptides like toxins and small proteins by searching for sub-structural motifs which are compatible with the derived disulphide bond connectivity. The user can obtain information about disulphide bonds of a particular protein of interest or probe the database for multiple disulphide bonded systems of particular connectivity.

The DSDBASE database has not only been updated to include 153,944 PDB entries, 216,096 native and 20,153,850 modelled disulphide bond segments, the current database provides resource to user-friendly search for multiple disulphide bond containing loops, along with annotation of their function using GO and active site residues. Further, it is now also possible to obtain three-dimensional models of disulphide-rich small proteins using an independent algorithm, RANMOD (Sowdhamini et al., 1993)that generates and examines random, but allowed backbone conformations to the polypeptide.


  1. DSDBASE is upgraded to search in PDB-Jan 2021 release.

  2. Peptide fragments of distinct loop sizes from various substructures at Non Redundant of 90% sequence identity is available for download.

  3. RANMOD procedure to model peptides that are rich in disulphides bond is available.

  4. GO annotations for Biological processes and Molecular functions are provided for the PDB hits.

  5. User can go to a PDB hit belonging to specific class of enzymes.

  6. Enhanced user interface with contextual help and easy navigation.

Distribution of Disulphide Bonds in DSDBASE Version 2.0

Dataset No. of Proteins Native Disulphides Modelled Disulphides Total Disulphides
Non-redundant_30 (Jan - 2021) 26,638 20,932 2,282,752 2,303,684
Non-redundant_90 (Jan - 2021) 43,200 51,932 5,012,608 5,064,540
Full database (Jan - 2021) 153,944 216,096 20,153,850 20,369,946

Distribution of Disulphide Bonds in DSDBASE Old Versions

Dataset No. of Proteins Native Disulphides Modelled Disulphides Total Disulphides
Non-redundant_25(April-2001) 1,131 950 46,568 47,518
Full Database (PDB April-2001) 13,513 22,588 1,491,597 1,514,185
Non-redundant_25(April-2002) 1,758 1,413 70,887 72,300
Full database (PDB July-2002) 17,163 28,141 1,973,898 2,002,039
Non-redundant_25(April-2003) 2,849 2,170 147,722 149,892
Full database (PDB April-2003) 19,612 31,657 2,353,960 2,385,617