Modification of potato cell wall pectin by the introduction of rhamnogalacturonan lyase and beta-galactosidase transgenes and their side effects

作者：Huang Jie Hong; Kortstee Anne; Dees Dianka C T; Trindade Luisa M; Schols Henk A; Gruppen Harry^*

来源：Carbohydrate Polymers, 2016, 144: 9-16.

DOI：10.1016/j.carbpol.2016.02.037

• Plant cell wall polysaccharides
• Starch removal
• Potato pectin
• Galactan side chains
• Potato mutant
• Solanum tuberosuma

Genes encoding pectic enzymes were introduced to wild-type potato Karnico. Cell wall materials were extracted from Karnico and transgenic lines expressing beta-galactosidase (beta-Gal-14 mutant) or rhamnogalacturonan lyase (RGL-18 mutant). After sequential extraction, beta-Gal-14 hot buffer-soluble solids (HBSS) of pectin contained 54% less galactose than Karnico HBSS, representing shorter galactan side chains. The individual pectin populations of beta-Gal-14 HBSS showed different modifications extended to the two sub-populations as obtained by ion-exchange chromatography. Compared to wild-type, RGL-18 HBSS contained 27% more galacturonic acid and 55% less Gal on fresh potato weight basis, which was due to the removal of galactan-rich rhamnogalacturonan I (RG-I) segments. All pectin populations of RGL-18 showed consistently low levels of RG-I segments. Transgenic modification showed side effects on the methyl-esterification and acetyl substitution of RGL-18 HBSS (DM = 53, DA = 21), but not of the beta-Gal-14HBSS in comparison to wild-type (DM = 29, DA = 54).

• 出版日期2016-6-25