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Updated: Aug 5, 2026
05:34
Applying Cheminformatics to Develop a Structure Searchable Database of Analytical Methods
Published on: June 6, 2025
A Two-Layer Structural Key Framework for Linking Compound Identifiers and MS/MS Evidence in Spectral Database
Kaiwen Deng1, Ran Liu1, Ruiping He1
1Shanghai Key Laboratory of Metabolic Remodeling and Health, Institute of Metabolism & Integrative Biology, Fudan University, Shanghai 200433, China.
Metabolites
|July 27, 2026
Summary
A new framework standardizes compound structures and links them to MS/MS spectral data. This improves metabolomics databases by organizing spectral evidence at stereo and connectivity levels for better compound identification.
Area of Science:
- Metabolomics
- Computational Chemistry
- Bioinformatics
Background:
- MS/MS spectral databases are crucial for compound identification in metabolomics.
- Challenges include linking compound identifiers, structures, and MS/MS data due to varied formats and stereochemistry.
- Standardized links are needed for accurate spectral database utility.
Purpose of the Study:
- To develop a two-layer structural key framework for linking compound identifiers and MS/MS evidence.
- To standardize chemical structures and create stereo and connectivity keys.
- To enhance the traceability and curation of spectral databases.
Main Methods:
- Utilized a Python-based RDKit workflow to standardize SMILES strings.
- Converted standardized structures into InChIKey-derived stereo keys and connectivity keys.
- Applied the framework to the Human Metabolome Database (HMDB) and the MassBank of North America (MoNA) database.
Main Results:
- The stereo key layer preserves compound identity and metadata at the stereoisomer level.
- The connectivity key layer groups MS/MS evidence at the molecular connectivity level.
- Integrated 217,920 HMDB entries and 144,591 MoNA spectra, increasing MS/MS evidence coverage.
Conclusions:
- The framework provides a bidirectionally traceable system for spectral database curation.
- It links compound identifiers, standardized structures, and MS/MS evidence at both stereo and connectivity levels.
- This approach avoids misassigning connectivity-level MS/MS evidence to stereo-specific identities.
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