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bioRxiv · 10.1101/2021.07.01.450702

Locality-sensitive hashing enables signal classification in high-throughput mass spectrometry raw data at scale

Abstract

Mass spectrometry is an important experimental technique in the field of proteomics. However, analysis of certain mass spectrometry data faces a combination of two challenges: First, even a single experiment produces a large amount of multi-dimensional raw data and, second, signals of interest are not single peaks but patterns of peaks that span along the different dimensions. The rapidly growing amount of mass spectrometry data increases the demand for scalable solutions. Existing approaches for signal detection are usually not well suited for processing large amounts of data in parallel or rely on strong assumptions concerning the signals properties. In this study, it is shown that locality-sensitive hashing enables signal classification in mass spectrometry raw data at scale. Through appropriate choice of algorithm parameters it is possible to balance false-positive and false-negative rates. On synthetic data, a superior performance compared to an intensity thresholding approach was achieved. The implementation scaled out up to 88 threads on real data. Locality-sensitive hashing is a desirable approach for signal classification in mass spectrometry raw data. Generated data and code are available at https://github.com/hildebrandtlab/mzBucket. Raw data is available at https://zenodo.org/record/5036526.

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BibTeXRIS

Bob, K., Teschner, D., Kemmer, T., Gomez-Zepeda, D., Tenzer, S., Schmidt, B., Hildebrandt, A.. 2021-07-02. Locality-sensitive hashing enables signal classification in high-throughput mass spectrometry raw data at scale. https://doi.org/10.1101/2021.07.01.450702

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