The XLMOD ontology is a structured, controlled vocabulary for cross-linking reagents and cross-linker related post-translational modifications used in cross-linking mass spectrometry experiments and derivatization reagents for GC-MS. Developed by the HUPO Proteomics Standards Initiative (PSI).

Its previous home was at within the mzIndentML repository at https://github.com/HUPO-PSI/mzIdentML/tree/master/cv but as of 2022-02-04 has been given its own home here.

The draft mapping file for the mzTab validator can be found at https://raw.githubusercontent.com/nilshoffmann/mzTab/580489542e89f4cf0d2925fda683ef2963f1e883/specification_document-developments/2_0-Metabolomics-Draft/mzTab_2_0-M_mapping.xml

Additional semi-structured information about xmlmod can be found at: https://github.com/HUPO-PSI/xlmod-CV/blob/main/xlmod.md

Anyone can request a new term be added to the controlled vocabulary by opening an issue or a pull request against this repository. We'd appreciate any help you can contribute when submitting a new term, from proposing the term name and description to defining its relationships and properties. Submitting the request already formatted as an OBO term is helpful too! Don't worry about finding an unused id string, that can be handled near the end.

If you're requesting multiple related terms, you can submit them in a single issue/pull request.