title: Rapid and sensitive quantification of C3- and C6-phosphoesters in starch by fluorescence-assisted capillary electrophoresis.
abstract: Phosphate groups are naturally present in starch at C3- or C6-position of the glucose residues and impact the structure of starch granules. Their precise quantification is necessary for understanding starch physicochemical properties and metabolism. Nevertheless, reliable quantification of Glc-3-P remains laborious and time consuming. Here we describe a capillary electrophoresis method for simultaneous measurement of both Glc-6-P and Glc-3-P after acid hydrolysis of starch. The sensitivity threshold was estimated at the fg scale, which is compatible with the analysis of less than a μg of sample. The method was validated by analyzing antisense potato lines deficient in SBEs, GWD or GBSS. We show that Glc-3-P content is altered in the latter and that these variations do not correlate with modifications in Glc-6-P content. We anticipate the method reported here to be an efficient tool for high throughput study of starch phosphorylation at both C3- and C6-position.
authors: Univ. Lille, CNRS, USR 3290-MSAP-Miniaturisation pour la Synthèse l'Analyse et la Protéomique, F-59000 Lille, France.
authors: Jeremy
authors: J
authors: Verbeke
authors: Univ. Lille, CNRS, USR 3290-MSAP-Miniaturisation pour la Synthèse l'Analyse et la Protéomique, F-59000 Lille, France.
authors: Christophe
authors: C
authors: Penverne
authors: Univ. Lille, CNRS, UMR 8576-UGSF-Unité de Glycobiologie Structurale et Fonctionnelle, F-59000 Lille, France.
authors: Christophe
authors: C
authors: D'Hulst
authors: Univ. Lille, CNRS, USR 3290-MSAP-Miniaturisation pour la Synthèse l'Analyse et la Protéomique, F-59000 Lille, France.
authors: Christian
authors: C
authors: Rolando
authors: Univ. Lille, CNRS, USR 3290-MSAP-Miniaturisation pour la Synthèse l'Analyse et la Protéomique, F-59000 Lille, France. Electronic address: nicolas.szydlowski@univ-lille1.fr.
authors: Nicolas
authors: N
authors: Szydlowski
mesh_terms: D019075:Electrophoresis, Capillary / Q000379:methods*; D006868:Hydrolysis; D010710:Phosphates / Q000032:analysis*; D013213:Starch / Q000737:chemistry*
chemical_list: D010710:Phosphates; D013213:Starch
keywords: Capillary electrophoresis; Glucose-3-phosphate; Glucose-6-phosphate; Phosphate; Starch