HRaDeX: high-resolution HDXโMS analysis made simple โ๏ธ๐งฌ
HDX-MS, protein dynamics, structural proteomics, HRaDeX, mass spectrometry, protein folding, bioinformatics tools
๐ Project highlights
- โ๏ธ New tool: HRaDeX (R package + web server)
- ๐งฌ Enables high-resolution HDXโMS analysis
- ๐ Reconstructs residue-level dynamics from peptide data
- ๐ Uses extended kinetic modeling (ZS model)
- ๐ฏ Validated on 4000+ peptides across multiple datasets
๐ New paper out! This one is all about turning messy HDXโMS data into something actually interpretable ๐
๐ Try it yourself (no excuses ๐)
HRaDeX is available as both a web application and an R package, allowing flexible use across workflows, from quick exploration to large-scale analysis.
๐ง Audio summary
HDXโMS + peptide overlap + kinetic modeling = ๐ตโ๐ซ
๐ So yes, this one also deserves a quick audio breakdown ๐ง
๐ฌ What is this about?
HRaDeX is a bioinformatics tool for analyzing hydrogenโdeuterium exchange mass spectrometry (HDXโMS) data, enabling reconstruction of protein dynamics at near residue-level resolution.
HDXโMS measures how proteins exchange hydrogen with deuterium over time, revealing:
- structural stability
- folding dynamics
- solvent accessibility
๐ But standard analysis is limited to peptide-level resolution, averaging signals across multiple residues.
๐จ The core limitation
Classic HDXโMS:
- โ loses residue-level detail
- โ averages overlapping signals
- โ makes precise interpretation difficult
๐ This is where HRaDeX comes in.
๐ง The idea behind HRaDeX
HRaDeX reconstructs high-resolution information using:
๐งฉ Overlapping peptides
- combines multiple fragments covering the same region
โ๏ธ Kinetic modeling
- fits uptake curves using extended ZS model
- separates:
- fast
- intermediate
- slow exchange components
- fast
๐ Each peptide becomes a mixture of dynamic populations.
๐จ Visualizing protein dynamics
One of the nicest features:
๐ RGB color encoding of exchange rates
- ๐ด fast (flexible)
- ๐ข intermediate
- ๐ต slow (structured)
โก๏ธ giving a single-view map of dynamics across the sequence
โ๏ธ How the workflow works
According to the workflow:
- โ
Filter invalid data
- ๐ง Detect โno exchangeโ regions
- ๐ Fit kinetic models
- ๐ฏ Select best model (BIC)
- ๐ Aggregate overlapping peptides
- ๐จ Map results to sequence/structure
โ๏ธ Two resolution strategies
HRaDeX provides:
1๏ธโฃ Shortest peptide
- assigns values from smallest fragment
2๏ธโฃ Weighted average
- integrates all overlapping peptides
๐ The combination enables higher resolution than standard HDXโMS
๐ Performance & validation
Tested extensively:
- โ๏ธ >4000 peptides
- ๐ very low fitting error (RSS)
- ๐ฏ ~4โ7% RMSE in reconstructed uptake
๐ Meaning: HRaDeX reliably reproduces experimental HDX behavior
๐งฌ What you can actually do with it
- map flexible vs stable regions
- detect binding interfaces
- study allosteric effects
- compare protein states
๐ Example: binding-induced conformational changes clearly visible in case studies
๐ Why this matters
This work bridges a major gap:
๐ from peptide-level data โ residue-level interpretation
It enables:
- better structural insight
- more precise protein dynamics analysis
- improved reproducibility
โ ๏ธ Limitations
- depends on peptide coverage
- requires good experimental design
- resolution limited if overlap is low
๐ Still a major step forward compared to standard pipelines
๐ BioGenies perspective
This work fits directly into our focus on:
- protein dynamics ๐งฌ
- structural interpretation โ๏ธ
- computational biology ๐
๐ and reinforces a key idea better models = more information from the same data
