title: SIRIUS: decomposing isotope patterns for metabolite identification.
abstract: BACKGROUND
  High-resolution mass spectrometry (MS) is among the most widely used technologies in metabolomics. Metabolites participate in almost all cellular processes, but most metabolites still remain uncharacterized. Determination of the sum formula is a crucial step in the identification of an unknown metabolite, as it reduces its possible structures to a hopefully manageable set.
  
  
  RESULTS
  We present a method for determining the sum formula of a metabolite solely from its mass and the natural distribution of its isotopes. Our input is a measured isotope pattern from a high resolution mass spectrometer, and we want to find those molecules that best match this pattern. Our method is computationally efficient, and results on experimental data are very promising: for orthogonal time-of-flight mass spectrometry, we correctly identify sum formulas for >90% of the molecules, ranging in mass up to 1000 Da.
authors.affiliation: Lehrstuhl für Bioinformatik, Friedrich-Schiller-Universität Jena, Jena, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Böcker
authors.forename: Matthias C
authors.initials: MC
authors.lastname: Letzel
authors.forename: Zsuzsanna
authors.initials: Z
authors.lastname: Lipták
authors.forename: Anton
authors.initials: A
authors.lastname: Pervukhin
mesh_terms: D000465:Algorithms; D007554:Isotopes / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods*; D055432:Metabolomics; D008970:Molecular Weight; D012984:Software
chemical_list: D007554:Isotopes