title: Characterization of glycogen and amino acid pool of Entamoeba histolytica by 13C-NMR spectroscopy.
abstract: Trophozoite extracts of axenic Entamoeba histolytica were investigated by natural-abundance 13C-NMR spectroscopy. The extracts were found to contain a high level of glycogen (30 mM glucose equivalents), which had a compact structure as suggested by alpha (1-->6) branch points every 5-6 glucose residues. As other major metabolites, we identified putrescine (9.5 mM) and the following free amino acids: tyrosine and phenylalanine (1 mM), glycine, lysine and methionine (2 mM), isoleucine (5 mM), proline and valine (6-7 mM), leucine (11 mM) and glutamate (22 mM). Glutamate and proline may serve, together with putrescine, as intracellular osmolytes.
authors.affiliation: Abteilung Mikrobiologie, Universität Osnabrück, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Bakker-Grunwald
authors.forename: J B
authors.initials: JB
authors.lastname: Martin
authors.forename: G
authors.initials: G
authors.lastname: Klein
mesh_terms: D000596:Amino Acids / Q000032:analysis / Q000378:metabolism*; D000818:Animals; D002247:Carbon Isotopes; D003470:Culture Media; D004748:Entamoeba histolytica / Q000378:metabolism*; D006003:Glycogen / Q000032:analysis / Q000737:chemistry / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods
chemical_list: D000596:Amino Acids; D002247:Carbon Isotopes; D003470:Culture Media; D006003:Glycogen