Abstract
Abstract Upon illumination, dark starved spinach leaves show a 50% reduction of 14 C-incorporation capacity into lipids. If 32 P-incorporation is measured, the reduction is 85% compared to controls. The relative labelling of the fatty acid residues in total lipids of normal leaves was 80 - 90% compared to 30 - 50% in the darkened material. The kinetics of 14 C-incorporation into lipids show that in the controls the majority of 14 C was located in the monogalactosyl diglyceride fraction while in the dark kept material phosphatidyl glycerol and phosphatidyl choline were more highly labelled. Corresponding with the changed incorporation capacity a decrease in fatty acid concen tration in the glycolipid fraction and a simultaneous increase in the phosphatide fraction in dark pretreated leaves is observed. An illumination period of 30 - 60 minutes at 2×10 4 lx brings these inverse values back to normal. The most rapid labelling occurred in a glycolipid fraction lacking galactose and having a slightly more hydrophilic character than monogalactosyl diglyceride. The molar ratio of sugar, glycerol and fatty acids in this fraction is 1 : 1 : 1 - 2. The label in the fatty acid residues of this lipid fraction was approximately 10% in dark kept but 90% in control leaves. From 14 C-incorporation behavior it is suggested that this lipid is a precursor of monogalactosyl diglyceride. The changes of the labelling pattern of lipids in leaves kept in prolonged darkness are similar to those obtained with 3-(3,4-dichlorophenyl) -1,1-dimethylurea treated Chlorella. A close connection of these effects to the decrease of photosynthetic capacity is therefore suspected. Also the observation that the concentration of α-linolenic acid, bound in the glycolipids, is reduced in dark kept material and increases upon subsequent light exposure, fits into this context. A pos sible explanation of these labelling shifts seems to be a pH shift in the various cell-compartments induced by light/dark treatment.
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Claims 19
Claim · model-written summary
Dark-starved spinach leaves had 50% less 14 C incorporation into lipids upon illumination.
- Taxon
- spinach
Spinacia oleraceae0 - Treatment
- dark starvede0
- Outcome
- 14 C-incorporation capacity into lipidse0
- Direction
- reductione0
- Value
- 50%e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Upon illumination, dark starved spinach leaves show a 50% reduction of 14 C-incorporation capacity into lipids”
Claim · model-written summary
Dark-starved leaves had 85% less 32 P incorporation versus controls.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- Dark Keptt0
- Outcome
- 32 P-incorporatione0
- Direction
- reductione0
- Value
- 85%e0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“If 32 P-incorporation is measured, the reduction is 85% compared to controls”
t0“Dark Kept Spinach Leaves”
Claim · model-written summary
Fatty acid residues in normal leaves had 80 - 90% relative labelling.
- Taxon
- SpinachSpinacia oleraceat0
- Material
- normal leavese0
- Outcome
- relative labelling of the fatty acid residues in total lipidse0
- Value
- 80 - 90%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The relative labelling of the fatty acid residues in total lipids of normal leaves was 80 - 90% compared to 30 - 50% in the darkened material”
t0“Spinach Leaves”
Claim · model-written summary
Darkened leaves had 30 - 50% relative fatty acid labelling.
- Taxon
- SpinachSpinacia oleraceat0
- Material
- darkened materiale0
- Outcome
- relative labelling of the fatty acid residues in total lipidse0
- Value
- 30 - 50%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The relative labelling of the fatty acid residues in total lipids of normal leaves was 80 - 90% compared to 30 - 50% in the darkened material”
t0“Spinach Leaves”
Claim · model-written summary
Control leaf 14 C was mainly in monogalactosyl diglyceride.
- Taxon
- SpinachSpinacia oleraceat0
- Outcome
- majority of 14 C was located in the monogalactosyl diglyceride fractione0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in the controls the majority of 14 C was located in the monogalactosyl diglyceride fraction”
t0“Spinach Leaves”
Claim · model-written summary
Dark kept leaves had more labelled phosphatidyl glycerol and phosphatidyl choline.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- dark kepte0
- Outcome
- phosphatidyl glycerol and phosphatidyl cholinee0
- Direction
- more highly labellede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“in the dark kept material phosphatidyl glycerol and phosphatidyl choline were more highly labelled”
t0“Spinach Leaves”
Claim · model-written summary
Dark pretreatment decreased fatty acid concentration in glycolipids.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- dark pretreatede0
- Outcome
- fatty acid concen tration in the glycolipid fractione0
- Direction
- decreasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a decrease in fatty acid concen tration in the glycolipid fraction and a simultaneous increase in the phosphatide fraction in dark pretreated leaves”
t0“Spinach Leaves”
Claim · model-written summary
Dark pretreatment increased fatty acid concentration in phosphatides.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- dark pretreatede0
- Outcome
- phosphatide fractione0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“a decrease in fatty acid concen tration in the glycolipid fraction and a simultaneous increase in the phosphatide fraction in dark pretreated leaves”
t0“Spinach Leaves”
Claim · model-written summary
Illumination for 30 - 60 minutes restored the inverse values.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- illumination period of 30 - 60 minutes at 2×10 4 lxe0
- Outcome
- inverse values back to normale0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“An illumination period of 30 - 60 minutes at 2×10 4 lx brings these inverse values back to normal”
t0“Spinach Leaves”
Claim · model-written summary
The most rapidly labelled fraction lacked galactose and was more hydrophilic.
- Taxon
- SpinachSpinacia oleraceat0
- Outcome
- most rapid labellinge0
- Qualifier
- glycolipid fraction lacking galactose and having a slightly more hydrophilic character than monogalactosyl diglyceridee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The most rapid labelling occurred in a glycolipid fraction lacking galactose and having a slightly more hydrophilic character than monogalactosyl diglyceride”
t0“Spinach Leaves”
Claim · model-written summary
Sugar:glycerol:fatty acid ratio of that lipid fraction was 1 : 1 : 1 - 2.
- Taxon
- SpinachSpinacia oleraceat0
- Outcome
- molar ratio of sugar, glycerol and fatty acidse0
- Value
- 1 : 1 : 1 - 2e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The molar ratio of sugar, glycerol and fatty acids in this fraction is 1 : 1 : 1 - 2”
t0“Spinach Leaves”
Claim · model-written summary
Fatty acid label in that fraction was approximately 10% in dark-kept leaves.
- Taxon
- SpinachSpinacia oleraceat0
- Material
- dark kepte0
- Outcome
- label in the fatty acid residues of this lipid fractione0
- Value
- approximately 10%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The label in the fatty acid residues of this lipid fraction was approximately 10% in dark kept but 90% in control leaves”
t0“Spinach Leaves”
Claim · model-written summary
Fatty acid label in that fraction was 90% in control leaves.
- Taxon
- SpinachSpinacia oleraceat0
- Material
- control leavese0
- Outcome
- label in the fatty acid residues of this lipid fractione0
- Value
- 90%e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The label in the fatty acid residues of this lipid fraction was approximately 10% in dark kept but 90% in control leaves”
t0“Spinach Leaves”
Claim · model-written summary
Authors suggested that this lipid precedes monogalactosyl diglyceride.
- Taxon
- SpinachSpinacia oleraceat0
- Outcome
- precursor of monogalactosyl diglyceridee0
- Qualifier
- 14 C-incorporation behaviore0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“From 14 C-incorporation behavior it is suggested that this lipid is a precursor of monogalactosyl diglyceride”
t0“Spinach Leaves”
Claim · model-written summary
Dark-leaf lipid labelling shifts resembled those in DCMU-treated Chlorella.
- Taxon
- SpinachSpinacia oleraceat0
- Outcome
- changes of the labelling pattern of lipidse0
- Comparator
- 3-(3,4-dichlorophenyl) -1,1-dimethylurea treated Chlorellae0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The changes of the labelling pattern of lipids in leaves kept in prolonged darkness are similar to those obtained with 3-(3,4-dichlorophenyl) -1,1-dimethylurea treated Chlorella”
t0“Spinach Leaves”
Claim · model-written summary
Glycolipid-bound α-linolenic acid decreased in dark-kept leaves.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- dark kepte0
- Outcome
- concentration of α-linolenic acid, bound in the glycolipidse0
- Direction
- reducede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the concentration of α-linolenic acid, bound in the glycolipids, is reduced in dark kept material and increases upon subsequent light exposure”
t0“Spinach Leaves”
Claim · model-written summary
Glycolipid-bound α-linolenic acid rose on subsequent light exposure.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- subsequent light exposuree0
- Outcome
- concentration of α-linolenic acid, bound in the glycolipidse0
- Direction
- increasese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the concentration of α-linolenic acid, bound in the glycolipids, is reduced in dark kept material and increases upon subsequent light exposure”
t0“Spinach Leaves”
Claim · model-written summary
Authors suspected links between lipid effects and reduced photosynthetic capacity.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- Dark Keptt0
- Outcome
- photosynthetic capacitye0
- Direction
- decreasee0
- Qualifier
- these effectse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A close connection of these effects to the decrease of photosynthetic capacity is therefore suspected”
t0“Dark Kept Spinach Leaves”
Claim · model-written summary
Authors proposed compartment pH shifts as an explanation of labelling shifts.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- light/dark treatmente0
- Outcome
- labelling shiftse0
- Qualifier
- pH shift in the various cell-compartmentse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A pos sible explanation of these labelling shifts seems to be a pH shift in the various cell-compartments induced by light/dark treatment”
t0“Spinach Leaves”
The same questions in other papers
light · molecular: metabolites · Spinacia oleracea (spinach)Positive and negative results
15 papers in the same direction as this paper · 13 in the opposite direction
- negative
- no effect
- negative
25 papers more in this group
See all 29 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.