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bioRxiv · 10.1101/291799

DIMEdb: an integrated database and web service for metabolite identification in direct infusion mass spectrometery

O'Shea, K.·Kattupalli, D.·Mur, L. A.·Hardy, N. W.·Misra, B. B.·Lu, C.
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Abstract

MotivationMetabolomics involves the characterisation, identification, and quantification of small molecules (metabolites) that act as the reaction intermediates of biological processes. Over the past few years, we have seen wide scale improvements in data processing, database, and statistical analysis tools. Direct infusion mass spectrometery (DIMS) is a widely used platform that is able to produce a global fingerprint of the metabolome, without the requirement of a prior chromatographic step - making it ideal for wide scale high-throughput metabolomics analysis. In spite of these developments, metabolite identification still remains a key bottleneck in untargeted mass spectrometry-based metabolomics studies. The first step of the metabolite identification task is to query masses against a metaboite database to get putative metabolite annotations. Each existing metabolite database differs in a number of aspects including coverage, format, and accessibility - often limiting the user to a rudimentary web interface. Manually combining multiple search results for a single experiment where there may be potentially hundreds of masses to investigate becomes an incredibly arduous task.\n\nResultsTo facilitate unified access to metabolite information we have created the Direct Infusion MEtabolite database (DIMEdb), a comprehensive web-based metabolite database that contains over 80,000 metabolites sourced from a number of renowned metabolite databases of which can be utilised in the analysis and annotation of DIMS data. To demostrate the efficacy of DIMEdb, a simple use case for metabolic identification is presented. DIMEdb aims to provide a single point of access to metabolite information, and hopefully facilitate the development of much needed bioinformatic tools.\n\nAvailabilityDIMEdb is freely available at https://dimedb.ibers.aber.ac.uk.\n\nContactkeo7@aber.ac.uk\n\nSupplementary informationSupplementary data are available at Bioinformatics online.

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O'Shea, K., Kattupalli, D., Mur, L. A., Hardy, N. W., Misra, B. B., Lu, C.. 2018-03-30. DIMEdb: an integrated database and web service for metabolite identification in direct infusion mass spectrometery. https://doi.org/10.1101/291799

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