Probing the Metabolic Network in Bloodstream-Form Trypanosoma brucei Using Untargeted Metabolomics with Stable Isotope Labelled Glucose

PLoS Pathogens

Muriel Mazet¹  Frédéric Bringaud¹  Pauline Morand¹  Yoann Millerioux¹  Marc Biran¹  Dong-Hyun Kim²  Ruwida Kamour³  Jana Anderson⁴  Darren J. Creek⁵  Achuthanunni Chokkathukalam⁶  Stefan K. Weidt⁶  Karl E. V. Burgess⁶  Rainer Breitling⁷  David G. Watson⁸  Eduard J. Kerkhoven⁹  Michael P. Barrett^1,10  Fiona Achcar^1,10 

[1] Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France;Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, University Park, Nottingham, United Kingdom;Department of Medicinal and Pharmaceutical Chemistry, Faculty of Pharmacy, University of Tripoli, Tripoli, Libya;Department of Public Health, Institute of Health and Wellbeing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom;Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Campus, Parkville, Victoria, Australia;Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom;Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom;Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom;Systems and Synthetic Biology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden;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

关键词: Trypanosoma;    Glucose metabolism;    Metabolic labeling;    Trypanosoma brucei gambiense;    Glucose;    Pyruvate;    Phosphates;    Ribose;   

DOI  :  10.1371/journal.ppat.1004689

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

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.

【 授权许可】

CC BY