title: Probing the metabolic network in bloodstream-form Trypanosoma brucei using untargeted metabolomics with stable isotope labelled glucose.
abstract: Metabolomics coupled with heavy-atom isotope-labelled glucose has been used to probe the metabolic pathways active in cultured bloodstream form trypomastigotes of Trypanosoma brucei, a parasite responsible for human African trypanosomiasis. Glucose enters many branches of metabolism beyond glycolysis, which has been widely held to be the sole route of glucose metabolism. Whilst pyruvate is the major end-product of glucose catabolism, its transamination product, alanine, is also produced in significant quantities. The oxidative branch of the pentose phosphate pathway is operative, although the non-oxidative branch is not. Ribose 5-phosphate generated through this pathway distributes widely into nucleotide synthesis and other branches of metabolism. Acetate, derived from glucose, is found associated with a range of acetylated amino acids and, to a lesser extent, fatty acids; while labelled glycerol is found in many glycerophospholipids. Glucose also enters inositol and several sugar nucleotides that serve as precursors to macromolecule biosynthesis. Although a Krebs cycle is not operative, malate, fumarate and succinate, primarily labelled in three carbons, were present, indicating an origin from phosphoenolpyruvate via oxaloacetate. Interestingly, the enzyme responsible for conversion of phosphoenolpyruvate to oxaloacetate, phosphoenolpyruvate carboxykinase, was shown to be essential to the bloodstream form trypanosomes, as demonstrated by the lethal phenotype induced by RNAi-mediated downregulation of its expression. In addition, glucose derivatives enter pyrimidine biosynthesis via oxaloacetate as a precursor to aspartate and orotate.
authors.affiliation: Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Campus, Parkville, Victoria, Australia.
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Creek
authors.affiliation: Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France.
authors.forename: Muriel
authors.initials: M
authors.lastname: Mazet
authors.affiliation: Wellcome Trust Centre of Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Fiona
authors.initials: F
authors.lastname: Achcar
authors.affiliation: Department of Public Health, Institute of Health and Wellbeing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Jana
authors.initials: J
authors.lastname: Anderson
authors.affiliation: Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, University Park, Nottingham, United Kingdom.
authors.forename: Dong-Hyun
authors.initials: DH
authors.lastname: Kim
authors.affiliation: Department of Medicinal and Pharmaceutical Chemistry, Faculty of Pharmacy, University of Tripoli, Tripoli, Libya.
authors.forename: Ruwida
authors.initials: R
authors.lastname: Kamour
authors.affiliation: Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France.
authors.forename: Pauline
authors.initials: P
authors.lastname: Morand
authors.affiliation: Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France.
authors.forename: Yoann
authors.initials: Y
authors.lastname: Millerioux
authors.affiliation: Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Biran
authors.affiliation: Systems and Synthetic Biology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden.
authors.forename: Eduard J
authors.initials: EJ
authors.lastname: Kerkhoven
authors.affiliation: Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Achuthanunni
authors.initials: A
authors.lastname: Chokkathukalam
authors.affiliation: Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Stefan K
authors.initials: SK
authors.lastname: Weidt
authors.affiliation: Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Karl E V
authors.initials: KE
authors.lastname: Burgess
authors.affiliation: Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom.
authors.forename: Rainer
authors.initials: R
authors.lastname: Breitling
authors.affiliation: Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom.
authors.forename: David G
authors.initials: DG
authors.lastname: Watson
authors.affiliation: Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Bringaud
authors.affiliation: Wellcome Trust Centre of Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom; Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom.
authors.forename: Michael P
authors.initials: MP
authors.lastname: Barrett
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D005947:Glucose / Q000378:metabolism*; D005990:Glycerol / Q000378:metabolism; D053858:Metabolic Networks and Pathways / Q000502:physiology*; D055432:Metabolomics / Q000379:methods; D010084:Oxidation-Reduction; D010427:Pentose Phosphate Pathway / Q000502:physiology; D019802:Succinic Acid / Q000378:metabolism; D014346:Trypanosoma brucei brucei / Q000378:metabolism*
chemical_list: D019802:Succinic Acid; D005947:Glucose; D005990:Glycerol