TY  - JOUR
A1  - Haebel, Sophie
A1  - Hejazi, Mahdi
A1  - Frohberg, Claus
A1  - Heydenreich, Matthias
A1  - Ritte, Gerhard
T1  - Mass spectrometric quantification of the relative amounts of C6 and C3 position phosphorylated glucosyl residues in starch
N2  - The quantification of phosphate bound to the C6 and C3 positions of glucose residues in starch has received increasing interest since the importance of starch phosphorylation for plant metabolism was discovered. The method described here is based on the observation that the isobaric compounds glucose-6-phosphate (Glc6P) and glucose-3- phosphate (Glc3P) exhibit significantly different fragmentation patterns in negative ion electrospray tandem mass spectrometry (MS/MS). A simple experiment involving collision-induced dissociation (CID) MS2 spectra of the sample and the two reference substances Glc3P and Glc6P permitted the quantification of the relative amounts of the two compounds in monosaccharide mixtures generated by acid hydrolysis of starch. The method was tested on well-characterized potato tuber starch. The results are consistent with those obtained by NMR analysis. In contrast to NMR, however, the presented method is fast and can be performed on less than 1 mg of starch. Starch samples of other origins exhibiting a variety of phosphorylation degrees were analyzed to assess the sensitivity and robustness of the method.
Y1  - 2008
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/30591
UR  - http://www.sciencedirect.com/science/journal/00032697
SN  - 0003-2697
ER  -