We have recently cloned a cDNA encoding sucrose:fructan 6-fructosyltransferase (6-SFT), a key enzyme of fructan synthesis forming the β-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 from fructans, synthesized the trisaccharide kestose and a series of unbranched fructans of the phlein type (β-2,6 linkages). Transformants of chicory, a plant naturally producing only unbranched fructans of the inulin type (β-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., Schellenbaum, L., Van Dun, K., Boller, T., & Wiemken, A. (1997). Fructan synthesis in transgenic tobacco and chicory plants expressing barley sucrose:fructan 6-fructosyltransferase. FEBS Letters, 400(3), 355–358. https://doi.org/10.1016/S0014-5793(96)01418-4