Fructose Polymers in Plants and Micro–Organisms

Polymers of fructose - fructans - are second only to starch as plant storage carbohydrates. In some taxa, notably the grasses, they dominate: they are turned over rapidly in leaves, and they can constitute half the weight of storage organs. They are also abundant in many micro-organisms. In spite of their biological importance, many aspects of their metabolism and function are poorly understood. Their synthesis is controversial, even the identity of the enzyme(s) involved being disputed, and their degradation comparatively little studied. Exactly what roles they fulfil which are not shared by starch and sucrose is far from clear, and claims that they are involved in drought or cold tolerance are hard to substantiate. This volume forms a collection of edited papers from the Third International Symposium on Fructan, which took place in Utah in July 1996.

Spis treści:
Part I. Structure
1. Fructan oligomers in Poa ampla
2. Structural diversity of fructan in relation to taxonomy of the Poaceae
Part II. Molecular Biology
3. Cytosolic expression of the Bacillus amyloliquefaciens SacB protein inhibits tissue development in transgenic tobacco and potato
4. The vacuolar sorting domain of sporamin transports GUS, but not levansucrase, to the plant vacuole
Part III. Enzymology
5. Synthesis of fructans by partially purified fructosyltransferase activities from Lolium rigidum
6. Biosynthesis in vitro of high-molecular-mass fructan by cell-free extracts from tuberous roots of Viguiera discolor (Asteraceae)
7. Fructan biosynthesis in excised leaves of Lolium temulentum, sucrose and fructan hydrolysis by a fructan-polymerising enzyme preparation
8. Fructan and fructan-metabolizing enzymes in the growth zone of barley leaves
9. Rise of fructan exohydrolase activity in stubble of Lolium perenne after defoliation is decreased by uniconazole, an inhibitor of the biosynthesis of gibberellins
10. Purification and substrate specificity of an extracellular fructanhydrolase from Lactobacillus paracasei
Part IV. Physiology
11. Patterns of solute in individual mesophyll, bundle sheath and epidermal cells of barley leaves induced to accumulate carbohydrate
12. Fructo-oligosaccharide content and fructosyltransferase activity during growth of onion bulbs
13. Fructan storage in tubers of Jerusalem artichoke, characterization of sink strength
14. Fructan metabolism in two species of Bromus subjected to chilling and water stress
15. Effects of short-term phosphorous deficiency on carbohydrate storage in sink and source leaves of barley (Hordeum vulgare)
16. Accumulation of fructans following oxygen deficiency stress in related plant species with different flooding tolerances
17. Fructan to nitrogen ratio as an indicator of nutrient stress in wheat crops
18. Growth and fructan contents in plants of Vernonia herbacea (Asteraceae) regenerated from rhizophores.