title: A metabolic trade-off between phosphate and glucose utilization in Escherichia coli.
abstract: Getting the most out of available nutrients is a key challenge that all organisms face. Little is known about how they optimize and balance the simultaneous utilization of multiple elemental resources. We investigated the effects of long-term phosphate limitation on carbon metabolism of the model organism Escherichia coli using chemostat cultures. We profiled metabolic changes in the growth medium over time and found evidence for an increase in fermentative metabolism despite the aerobic conditions. Using full-genome sequencing and competition experiments, we found that fitness under phosphate-limiting conditions was reproducibly increased by a mutation preventing flux through succinate in the tricarboxylic acid cycle. In contrast, these mutations reduced competitive ability under carbon limitation, and thus reveal a conflicting metabolic benefit in the role of the TCA cycle in environments limited by inorganic phosphate and glucose.
authors.affiliation: Department of Surgery and Cancer, Imperial College London, London SW7 2AZ, UK. volker.behrends05@imperial.ac.uk j.bundy@imperial.ac.uk.
authors.forename: Volker
authors.initials: V
authors.lastname: Behrends
authors.forename: Ram P
authors.initials: RP
authors.lastname: Maharjan
authors.forename: Ben
authors.initials: B
authors.lastname: Ryall
authors.forename: Lu
authors.initials: L
authors.lastname: Feng
authors.forename: Bin
authors.initials: B
authors.lastname: Liu
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.forename: Jacob G
authors.initials: JG
authors.lastname: Bundy
authors.forename: Thomas
authors.initials: T
authors.lastname: Ferenci
mesh_terms: D002244:Carbon / Q000378:metabolism*; D002952:Citric Acid Cycle; D003470:Culture Media; D004926:Escherichia coli / Q000502:physiology*; D029968:Escherichia coli Proteins / Q000235:genetics* / Q000378:metabolism; D005285:Fermentation; D056084:Genetic Fitness; D016680:Genome, Bacterial; D009154:Mutation; D010710:Phosphates / Q000378:metabolism*; D017422:Sequence Analysis, DNA; D019802:Succinic Acid / Q000378:metabolism
chemical_list: D003470:Culture Media; D029968:Escherichia coli Proteins; D010710:Phosphates; D002244:Carbon; D019802:Succinic Acid