3 research outputs found
Fructan synthesis is inhibited by phosphate in warm-grown, but not in cold-treated,excised barley leaves.
The inhibition by phosphate of fructan accumulation has been investigated in warm3
grown and cold-treated barley (Hordeum vulgare L.) plants.
• Detached leaves were incubated in water or phosphate for 24 h under lighting or in
darkness. Fructosyltransferase, sucrose phosphate synthase (SPS) and cytosolic
fructose- 1, 6 - bisphosphatase (FBPase) activities were subsequently analysed, as
well as the content of carbohydrates, hexose-phosphates, phosphate, amino acids and
protein.
• In warm-grown leaves, phosphate decreased fructan accumulation and total carbon in
carbohydrates and did not affect protein contents. Phosphate increased hexose
phosphates, phosphate and amino acids. Fructosyltransferase and FBPase activities
were not affected by phosphate feeding, while SPS activity was inhibited by
phosphate in incubations both in light and in darkness. In cold-treated leaves, which
prior to incubation had higher SPS activities than warm-grown leaves, phosphate had no inhibitory effect on fructan accumulation, carbohydrate content or total carbon in carbohydrates. SPS and FBPase activities were unaffected by phosphate.
• The results indicate that phosphate decreases fructan accumulation through an
inhibition of SPS whenever this activity is not high prior to a rise in phosphate
content.R. M. had a Ramón y Cajal research contract, and S.K. was the recipient of a grant
for stays of foreign researchers in Spain, both from the Ministry of Education, Science
and Sport. This work has been funded by the Junta de Castilla y León (Project
CSI19/03).Peer reviewe
Fructan synthesis is inhibited by phosphate in warm-grown, but not in cold-treated,excised barley leaves.
The inhibition by phosphate of fructan accumulation has been investigated in warm3
grown and cold-treated barley (Hordeum vulgare L.) plants.
• Detached leaves were incubated in water or phosphate for 24 h under lighting or in
darkness. Fructosyltransferase, sucrose phosphate synthase (SPS) and cytosolic
fructose- 1, 6 - bisphosphatase (FBPase) activities were subsequently analysed, as
well as the content of carbohydrates, hexose-phosphates, phosphate, amino acids and
protein.
• In warm-grown leaves, phosphate decreased fructan accumulation and total carbon in
carbohydrates and did not affect protein contents. Phosphate increased hexose
phosphates, phosphate and amino acids. Fructosyltransferase and FBPase activities
were not affected by phosphate feeding, while SPS activity was inhibited by
phosphate in incubations both in light and in darkness. In cold-treated leaves, which
prior to incubation had higher SPS activities than warm-grown leaves, phosphate had no inhibitory effect on fructan accumulation, carbohydrate content or total carbon in carbohydrates. SPS and FBPase activities were unaffected by phosphate.
• The results indicate that phosphate decreases fructan accumulation through an
inhibition of SPS whenever this activity is not high prior to a rise in phosphate
content.R. M. had a Ramón y Cajal research contract, and S.K. was the recipient of a grant
for stays of foreign researchers in Spain, both from the Ministry of Education, Science
and Sport. This work has been funded by the Junta de Castilla y León (Project
CSI19/03).Peer reviewe