Fructan synthesis in transgenic tobacco and chicory plants expressing barley sucrose: fructan 6-fructosyltransferase.
We have recently cloned a cDNA encoding sucrose:fructan 6-fructosyltransferase (6-SFT), a key enzyme of fructan synthesis forming the beta-2,6 linkages typical of the grass fructans, graminans and phleins [Sprenger et al. (1995) Proc. Natl. Acad. Sci. USA 92, 11652-11656]. Here we report functional expression of 6-SFT from barley in transgenic tobacco and chicory. Transformants of tobacco, a plant naturally unable to form fructans, synthesized the trisaccharide kestose and a series of unbranched fructans of the phlein type (beta-2,6 linkages). Transformants of chicory, a plant naturally producing only unbranched fructans of the inulin type (beta-2,1 linkages), synthesized in addition branched fructans of the graminan type, particularly the tetrasaccharide bifurcose which is also a main fructan in barley leaves.
Sprenger
N
N
Department of Botany, University of Basel, Switzerland.
Schellenbaum
L
L
van Dun
K
K
Boller
T
T
Wiemken
A
A
D005630:Fructans / Q000096:biosynthesis*; D006602:Hexosyltransferases / Q000235:genetics / Q000378:metabolism*; D001467:Hordeum / Q000201:enzymology*; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000378:metabolism*; D010947:Plants, Toxic; D014026:Nicotiana / Q000201:enzymology / Q000378:metabolism*; D014170:Transformation, Genetic
D005630:Fructans; D006602:Hexosyltransferases; C097181:sucrose - fructan 6-fructosyltransferase