MIDAS

- Deprecated

Version: 1.1

Website

http://midas.omicsbio.org/

Description

Metabolite Identification via Database Searching (MIDAS) is a database searching tool for metabolite identification of LC-MS/MS data acquired from high resolution mass spectrometers (TOF, Orbitrap). The MetaCyc database or a custom database of metabolites can be searched to find metabolite matches. For metabolite-spectrum match (MSM) evaluation a three-level fragmentation tree is calculated for the candidate metabolite. Firstly the measured precursor m/z is compared to the database to find candidate matches. The first level fragmentation tree is then generated and traversed by depth-first search (DFS). When a fragment is generated three charged forms are considered: [F]+, [F+H]+ and [F+H]2+ (and opposite in negative ion mode). The m/z of the fragment is generated and its plausibility is calculated. MSM are scored by comparing the observed spectrum to the calculated spectrum using a modified dot function. Candidates are ranked by their MSM scores.

Functionality

• Annotation

Instrument Data Type

• Annotation/MS/Level 2a - Library Spectrum Match

Approaches

• MS/LC-MS/LC-MS/MS

Computer Skills

Basic

Software Type

• Web Based

Interface

• Web User Interface

Operating System (OS)

• Unix/Linux
• Mac OS
• Windows

Language

Python

Dependencies

N/A

Input Formats - Open

.mzML, .ft2

Input Formats - Proprietary

N/A

Published

2014

Last Updated

2014

License

Paper

http://www.ncbi.nlm.nih.gov/pubmed/25157598

PMID

25157598