title: METATOOL: for studying metabolic networks.
abstract: BACKGROUND
  To reconstruct metabolic pathways from biochemical and/or genome sequence data, the stoichiometric and thermodynamic feasibility of the pathways has to be tested. This is achieved by characterizing the admissible region of flux distributions in steady state. This region is spanned by what can be called a convex basis. The concept of 'elementary flux modes' provides a mathematical tool to define all metabolic routes that are feasible in a given metabolic network. In addition, we define 'enzyme subsets' to be groups of enzymes that operate together in fixed flux proportions in all steady states of the system.
  
  
  RESULTS
  Algorithms for computing the convex basis and elementary modes developed earlier are briefly reviewed. A newly developed algorithm for detecting all enzyme subsets in a given network is presented. All of these algorithms have been implemented in a novel computer program named METATOOL, whose features are outlined here. The algorithms are illustrated by an example taken from sugar metabolism.
  
  
  BACKGROUND
  METATOOL is available from ftp://bmsdarwin.brookes.ac. uk/pub/software/ibmpc/metatool.
  
  
  BACKGROUND
  http://www. biologie.hu-berlin.de/biophysics/Theory/tpfeiffer/metatoo l.html
authors.affiliation: Humboldt University Berlin, Institute of Biology, Invalidenstrasse 42, D-10115 Berlin, Germany. Tpfeiffer@bp.biologie.hu-berlin.de
authors.forename: T
authors.initials: T
authors.lastname: Pfeiffer
authors.forename: I
authors.initials: I
authors.lastname: Sánchez-Valdenebro
authors.forename: J C
authors.initials: JC
authors.lastname: Nuño
authors.forename: F
authors.initials: F
authors.lastname: Montero
authors.forename: S
authors.initials: S
authors.lastname: Schuster
mesh_terms: D000465:Algorithms; D050260:Carbohydrate Metabolism; D004798:Enzymes / Q000378:metabolism; D006019:Glycolysis; D008660:Metabolism; D008954:Models, Biological; D010427:Pentose Phosphate Pathway; D012984:Software
chemical_list: D004798:Enzymes