Disulfide bonds in protein structures are covalent bonds between the sulfur atoms of cysteine residues.
They play an important role in the stability and folding of proteins.
Disulfide bonds are annotated by SSBOND records in the PDB file and in the _struct_conn category of the mmCIF file.
This search allows querying the PDB by the total number of disulfide bonds in all chains of asymmetric unit.
The RCSB PDB (citation) is managed by two members of the Research Collaboratory for Structural Bioinformatics:
RCSB PDB is a member of the
The RCSB PDB is funded by a grant (DBI-1338415) from the
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National Institutes of Health, and the
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