Xylogliicae- and cello-oligosaccharides: Antagonists of the growth-promoting effect of H+ |
| |
Authors: | Ester P. Lorences Gordon J. McDougall Stephen C. Fry |
| |
Affiliation: | Dept of Botany, Univ. of Edinburgh, The King's Buildings, Mayfield Road, Edinburgh EH9 3JH, UK. |
| |
Abstract: | Xyloglucan-oligosaccharides and cello-oligosaccharides, both of which are potential products of the action of cellulase on plant cell wail polysaccharides, inhibited acid-induced elongation in pea ( Pisum sativum L. cv. Alaska) stem segments. Xyloglucan-derived nonasaccharide (XG9; Glc4-Xyl3)Gal-Fuc) and decasaccharide (XG10; Glc4-Xyl3-Gal2-Fue) inhibited acid-induced growth at 1.0 and 0.1 n M , respectively, whereas the heptasaccharide (XG7; Glc4-Xyl3) and octasaccharide (XG8; Glc4-Xyl3-Gal)2 which lack L-fucose, did not. XG9 at 1 n M inhibited acid-induced growth as effectively as it inhibits auxin-induced elongation. This suggests that XG9's effect as an inhibitor of auxin action is not mediated by a suppresion of H+-efflux, but rather that XG9 blocks some step that is common to the action of both auxin and H+ on growth. Cello-oligosaccharides (degree of polymerisation 4–7) also inhibited acid-induced growth at 10 n M ; these are therefore a new class of possible oligosaccha-rin. The inhibitory effect of xyloglucan- and cellooligosaccharides on acid-induced growth was rapidly reversed by washing. |
| |
Keywords: | Acid growth auxin cellulase oligosaccharin pea Pisum sativum |
|
|