Biochemistry and physiology of raffinose family oligosaccharides and galactosyl cyclitols in seeds

By T. Peterbauer, Andreas Richter. Seed Science Research, 2001

349 citations recorded by the source corpus.

Abstract Raffinose family oligosaccharides (RFOs) are of almost ubiquitous occurrence in plant seeds. They accumulate during seed development and disappear rapidly during germination. The biosynthesis of raffinose, the first member of the series, proceeds by addition of a galactosyl unit to sucrose. Galactinol, a galactosyl derivative of myo-inositol, acts as a galactosyl donor. It is synthesized from UDP-D-GALACTOSE AND MYO-INOSITOL. STACHYOSE, VERBASCOSE AND AJUGOSE, THE NEXT HIGHER RFOS, ARE EITHER SYNTHESIZED BY GALACTINOL-DEPENDENT GALACTOSYLTRANSFERASES OR BY TRANSFER OF GALACTOSYL UNITS BETWEEN TWO RFO MOLECULES. IN SEEDS, THE METABOLISM OF METHYLATED INOSITOLS, SUCH AS D-ononitol and D-pinitol, is linked with the RFO pathway. In contrast to myo-inositol, these cyclitols are galactosylated by transfer of galactosyl residues from galactinol and not from UDP-D-galactose. However, the resulting galactosyl cyclitols can replace galactinol as galactosyl donors for the biosynthesis of stachyose. These recently discovered branches of the RFO pathway are active in seeds of a range of crop species, especially in legumes. We focus here on the biochemistry and molecular biology of the enzymes of RFO and galactosyl cyclitol biosynthesis. The metabolic control and hormonal regulation of the pathway during seed development and germination is discussed. The controversial role of α-galactosidases, which are believed to hydrolyse RFOs during germination, is reviewed critically.

Subfields: Nutrition and Dietetics, Plant Science

View Paper: https://www.semanticscholar.org/paper/7e3d37f757a59620ab128dbea869a17494903a3c

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Nutrition and Dietetics

1. Hyun‐Jung Chung
2. M. Martín-Cabrejas
3. Alberta N. A. Aryee
4. M. V. Vaz Patto
5. J. Boye
6. C. Jonak
7. R. Amarowicz
8. V. Raboy

In Plant Science

1. M. V. Vaz Patto
2. Y. Yabuta
3. A. Nishizawa
4. S. Shigeoka
5. C. Jonak
6. V. Raboy
7. Julia Krasensky
8. G. Kaur

Citations in the corpus

• Approaches and challenges to engineering seed phytate and total phosphorus (2009, positive): “The pathways to phytic acid and the soluble seed oligosaccharides including the raffinosaccharide series, galactosyl derivatives of sucrose, and the galactosyl derivatives of cyclitols (in turn derivatives of inositol), all utilize inositol [43,97,98].”
• Galactinol and Raffinose Constitute a Novel Function to Protect Plants from Oxidative Damage1[W][OA] (2008, background): “As shown in Figure 1, RFOs are synthesized from Suc by the subsequent addition of activated Gal moieties donated by galactinol (Peterbauer and Richter, 2001).”
• Achievements and Challenges in Improving the Nutritional Quality of Food Legumes (2015, background): “Much is known about the temporal expression and nature of the enzymes involved in the biosynthesis of seed oligosaccharides, with DNA sequence information available for galactinol, raffinose and stachyose synthases from a number of sources (Peterbauer and Richter, 2001).”
• Drought, salt, and temperature stress-induced metabolic rearrangements and regulatory networks (2012, positive): “Sequential addition of galactose units, provided by galactinol, to sucrose leads to the formation of raffinose and higher order RFO (Peterbauer and Richter, 2001).”