title: Expression of an (Engineered) 4,6-α-Glucanotransferase in Potato Results in Changes in Starch Characteristics.
abstract: Starch structure strongly influences starch physicochemical properties, determining the end uses of starch in various applications. To produce starches with novel structure and exploit the mechanism of starch granule formation, an (engineered) 4, 6-α-glucanotransferase (GTFB) from Lactobacillus reuteri 121 was introduced into two potato genetic backgrounds: amylose-containing line Kardal and amylose-free mutant amf. The resulting starches showed severe changes in granule morphology regardless of genetic backgrounds. Modified starches from amf background exhibited a significant increase in granule size and starch phosphate content relative to the control, while starches from Kardal background displayed a higher digestibility, but did not show changes in granule size and phosphate content. Transcriptome analysis revealed the existence of a mechanism to restore the regular packing of double helices in starch granules, which possibly resulted in the removal of novel glucose chains potentially introduced by the (engineered) GTFB. This amendment mechanics would also explain the difficulties to detect alterations in starch fine structure in the transgenic lines.
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research, P.O. Box 386, 6700, AJ, Wageningen. The Netherlands.|National Centre for Vegetable Improvement (Central China), Key Laboratory of Horticultural Plant Biology, Ministry of Education, Huazhong Agricultural University, Wuhan, 430070, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Xu
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research, P.O. Box 386, 6700, AJ, Wageningen. The Netherlands.
authors.forename: Annemarie
authors.initials: A
authors.lastname: Dechesne
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research, P.O. Box 386, 6700, AJ, Wageningen. The Netherlands.
authors.forename: Richard G F
authors.initials: RG
authors.lastname: Visser
authors.affiliation: Wageningen UR Plant Breeding, Wageningen University and Research, P.O. Box 386, 6700, AJ, Wageningen. The Netherlands.
authors.forename: Luisa M
authors.initials: LM
authors.lastname: Trindade
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D015870:Gene Expression; D006004:Glycogen Debranching Enzyme System / Q000096:biosynthesis* / Q000235:genetics; D052200:Limosilactobacillus reuteri / Q000201:enzymology / Q000235:genetics*; D030821:Plants, Genetically Modified / Q000235:genetics / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D011198:Solanum tuberosum / Q000235:genetics / Q000378:metabolism; D013213:Starch / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D006004:Glycogen Debranching Enzyme System; D011994:Recombinant Proteins; D013213:Starch; C020569:4 alpha-glucanotransferase