title: Evaluation of isotope discrimination in (13)C-based metabolic flux analysis.
abstract: In a (13)C experiment for metabolic flux analysis ((13)C MFA), we examined isotope discrimination by measuring the labeling of glucose, amino acids, and hexose monophosphates via mass spectrometry. When Escherichia coli grew in a mix of 20% fully labeled and 80% naturally labeled glucose medium, the cell metabolism favored light isotopes and the measured isotopic ratios (δ(13)C) were in the range of -35 to -92. Glucose transporters might play an important role in such isotopic fractionation. Flux analysis showed that both isotopic discrimination and isotopic impurities in labeled substrates could affect the solution of (13)C MFA.
authors: Department of Energy, Environmental and Chemical Engineering, Washington University, St. Louis, MO 63130, USA.
authors: Xueyang
authors: X
authors: Feng
authors: Yinjie J
authors: YJ
authors: Tang
mesh_terms: D000596:Amino Acids / Q000737:chemistry / Q000378:metabolism*; D057486:Carbon Cycle; D002247:Carbon Isotopes / Q000032:analysis / Q000378:metabolism; D004926:Escherichia coli / Q000737:chemistry / Q000378:metabolism; D005947:Glucose / Q000737:chemistry / Q000378:metabolism*; D006600:Hexosephosphates / Q000737:chemistry; D013058:Mass Spectrometry
chemical_list: D000596:Amino Acids; D002247:Carbon Isotopes; D006600:Hexosephosphates; D005947:Glucose