Expression of alternansucrase in potato plants.
Alternan, which consists of alternating alpha-(1-->3)/alpha-(1-->6)-linked glucosyl residues, was produced in potato tubers by expressing a mature alternansucrase (Asr) gene from Leuconostoc mesenteroides NRRL B-1355 in potato. Detection of alternan was performed by enzyme-linked immunosorbent assay in tuber juices, revealing a concentration between 0.3 and 1.2 mg g(-1) fresh wt. The Asr transcript levels correlated well with alternan accumulation in tuber juices. It appeared that the expression of sucrose-regulated starch-synthesizing genes (ADP-glucose pyrophosphorylase subunit S and granule-bound starch synthase I) was down-regulated. Despite this, the physico-chemical properties of the transgenic starches were unaltered. These results are compared to those obtained with other transgenic potato plants producing mutan [alpha-(1-->3)-linked glucosyl residues] and dextran [alpha-(1-->6)-linked glucosyl residues].
Kok-Jacon
Géraldine A
GA
Graduate School Experimental Plant Sciences, Laboratory of Plant Breeding, Wageningen University, Wageningen, The Netherlands.
Vincken
Jean-Paul
JP
Suurs
Luc C J M
LC
Wang
Denong
D
Liu
Shaoyi
S
Visser
Richard G F
RG
D015536:Down-Regulation / Q000235:genetics; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D005822:Genetic Vectors; D005936:Glucans / Q000378:metabolism; D051599:Glucose-1-Phosphate Adenylyltransferase / Q000235:genetics; D016695:Glycosyltransferases / Q000235:genetics*; D030821:Plants, Genetically Modified; D011198:Solanum tuberosum / Q000201:enzymology* / Q000235:genetics*; D013213:Starch / Q000378:metabolism / Q000648:ultrastructure; D013214:Starch Synthase / Q000235:genetics
D005936:Glucans; C439358:alternan; D013213:Starch; D016695:Glycosyltransferases; C033837:alternansucrase; D013214:Starch Synthase; D051599:Glucose-1-Phosphate Adenylyltransferase