title: Determination of biomass composition of Catharanthus roseus hairy roots for metabolic flux analysis.
abstract: Metabolic flux analysis is a powerful diagnostic tool in metabolic engineering, and determination of biomass composition is indispensable to accurate flux evaluation. We report the elemental and biomolecular composition of Catharanthus roseus hairy roots, a pharmaceutically significant plant system and an important metabolic engineering target. The molecular formula of the organic material in the hairy roots was C12.0H22.7N0.4O7.6 during mid-exponential growth. The abundances of lipids, lignin, cellulose, hemicellulose, starch, protein, proteinogenic amino acids, mineral ash, and moisture in the biomass were quantified. Analysis of water-soluble components of the biomass with 1-D 13C and 2-D [1H,1H] correlation (COSY) NMR spectroscopy revealed that the water-soluble components were composed almost entirely of -glucans. Agropine, a frequently reported hairy root biomass component, was not detected. Our measurements of the biomass components quantified 83.6 +/- 9.3% (w/w) of the biomass. Together with previously reported abundances of indole alkaloids, we accounted for at least 85.9 +/- 11.6% (w/w) of the carbon in the biomass, which enabled the precise determination of 12 biomass synthesis fluxes.
authors.affiliation: Department of Chemical and Biological Engineering, Iowa State University, 3031, Sweeney Hall, Ames, Iowa 50011, USA.
authors.forename: Ganesh
authors.initials: G
authors.lastname: Sriram
authors.forename: Omar
authors.initials: O
authors.lastname: González-Rivera
authors.forename: Jacqueline V
authors.initials: JV
authors.lastname: Shanks
mesh_terms: D001704:Biopolymers / Q000378:metabolism*; D002244:Carbon / Q000032:analysis*; D030008:Catharanthus / Q000378:metabolism*; D003198:Computer Simulation; D008954:Models, Biological; D018517:Plant Roots / Q000378:metabolism*; D020543:Proteome / Q000032:analysis*
chemical_list: D001704:Biopolymers; D020543:Proteome; D002244:Carbon