Generation of phytate-free seeds in Arabidopsis through disruption of inositol polyphosphate kinases - PubMed (original) (raw)

Fig. 2.

IP metabolism of IPK mutants. (A) Nonradioactive mass IP analysis of mature dessicated seed extracts. Seed extracts were separated by an IonPac AS7 anion-exchange column, detected by metal-dye chelation, and measured at 550 nm. Data points are plotted as negative absorbance values. (B) Wild-type and IPK mutant seeds were germinated in liquid MS salts with 400 μCi/ml [3H]-_myo_-inositol for 6 days, and IPs were harvested from seedlings and analyzed by Partisphere strong anion exchange HPLC. Representative chromatograms for each genotype are shown and indicated at the right. The chemical identity of IP3 a is currently unknown. Eighty percent of IP4 a is I(3,4,5,6)P4, and 20% is I(1,3,4,6)P4 and/or I(1,4,5,6)P4. IP5 a is I(1,3,4,5,6)P5. IP4b is I(1,3,4,6)P4 and/or I(1,4,5,6)P4. IP5b is I(1,2,3,4,6)P5. IP5c is either I(1,2,4,5,6)P5 or its enantiomer I(2,3,4,5,6)P5. Sometimes slight alterations in IP migration were observed and are due to different strong anion exchange columns. In all cases, the IPs are compared with known standards.