dbGSH: a database of S-glutathionylation.

S-glutathionylation, the reversible protein posttranslational modification (PTM) that generates a mixed disulfide bond between glutathione and cysteine residue, critically regulates protein activity, stability and redox regulation. Due to its importance in regulating oxidative/nitrosative stress and balance in cellular response, a number of methods have been rapidly developed to study S-glutathionylation, thus expanding the dataset of experimentally determined glutathionylation sites. However, there is currently no database dedicated to the integration of all experimentally verified S-glutathionylation sites along with their characteristics or structural or functional information. Thus, the dbGSH database has been created to integrate all available datasets and to provide the relevant structural analysis. As of January 31, 2014, dbGSH has manually collected 42200 experimentally verified S-glutathionylated peptides from 169 research articles using a text-mining approach. To solve the problem of heterogeneity of the data collected from different sources, the sequence identity of the reported S-glutathionylated peptides is mapped to UniProtKB protein entries. To delineate the structural correlations and consensus motifs of these S-glutathionylation sites, the dbGSH database also provides structural and functional analyses, including the motifs of substrate sites, solvent accessibility, protein secondary and tertiary structures, protein domains and gene ontology.