title: Detecting the Significant Flux Backbone of Escherichia coli metabolism.
abstract: The heterogeneity of computationally predicted reaction fluxes in metabolic networks within a single flux state can be exploited to detect their significant flux backbone. Here, we disclose the backbone of Escherichia coli, and compare it with the backbones of other bacteria. We find that, in general, the core of the backbones is mainly composed of reactions in energy metabolism corresponding to ancient pathways. In E. coli, the synthesis of nucleotides and the metabolism of lipids form smaller cores which rely critically on energy metabolism. Moreover, the consideration of different media leads to the identification of pathways sensitive to environmental changes. The metabolic backbone of an organism is thus useful to trace simultaneously both its evolution and adaptation fingerprints.
authors.affiliation: Departament de Ciència dels Materials i Química Física, Universitat de Barcelona, Spain.
authors.forename: Oriol
authors.initials: O
authors.lastname: Güell
authors.affiliation: Departament de Ciència dels Materials i Química Física, Universitat de Barcelona, Spain.
authors.forename: Francesc
authors.initials: F
authors.lastname: Sagués
authors.affiliation: Department de Física de la Matèria Condensada, Universitat de Barcelona, Spain.|University of Barcelona Institute of Complex Systems (UBICS), Universitat de Barcelona, Spain.|ICREA, Barcelona, Spain.
authors.forename: M Ángeles
authors.initials: MÁ
authors.lastname: Serrano
mesh_terms: D000465:Algorithms; D001419:Bacteria / Q000378:metabolism; D004926:Escherichia coli / Q000254:growth & development* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000378:metabolism; D053858:Metabolic Networks and Pathways; D008954:Models, Biological; D049490:Systems Biology / Q000379:methods*
chemical_list: D029968:Escherichia coli Proteins
keywords: disparity filter; flux balance analysis; metabolic backbones; metabolic networks