Abstract
Two peaks of hexosediphosphatase activity could be separated from spinach leaves by DEAE-Sephadex chromatography. Since extracts of isolated intact chloroplasts exhibited only one peak of enzyme activity we conclude that spinach leaves contain two hexosediphosphatases, one in the chloroplasts and one in the cytoplasm. Purified hexosediphosphatase prepared according to Racker and Schroeder and Buchanan et al. contained only the chloroplast enzyme. Both enzymes catalyse specifically the hydrolysis of fructose 1,6-bisphosphate to fructose 6-phosphate and inorganic phosphate and show an absolute requirement for Mg2®. The concentration·, of Mg2® has no effect on the pH-optimum of the. cytoplasmic enzyme. The cytoplasmic hexosediphosphatase differs from the chloroplast enzyme in the following properties: assayed with 10 mM Mg2® the pH optimum is lower, (7.5 for the cytoplasmic and 8.5 for the chloroplast enzyme) and the affinity for fructose bisphosphate at the pH optimum is greater. In contrast to the chloroplast enzyme, the cytoplasmic enzyme is not activated by dithiothreitol or cystamine, but is inhibited by adenosine 5'-phosphate.
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Claims 11
Claim · model-written summary
Spinach leaf extracts yielded two peaks of hexosediphosphatase activity.
- Taxon
- spinach
Spinacia oleraceae0 - Organ / stage
- leavese0
- Gene
- hexosediphosphatasee0
- Outcome
- Two peaks of hexosediphosphatase activitye0
- Value
- Two peakse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Two peaks of hexosediphosphatase activity could be separated from spinach leaves by DEAE-Sephadex chromatography.”
Claim · model-written summary
Spinach leaves contain chloroplast and cytoplasmic hexosediphosphatases.
- Taxon
- spinachSpinacia oleraceae0
- Organ / stage
- leavese0
- Gene
- hexosediphosphatasese0
- Outcome
- two hexosediphosphatasese0
- Value
- twoe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“spinach leaves contain two hexosediphosphatases, one in the chloroplasts and one in the cytoplasm.”
Claim · model-written summary
The purified enzyme preparations contained only chloroplast hexosediphosphatase.
- Taxon
- SpinachSpinacia oleraceat0
- Gene
- hexosediphosphatasee0
- Outcome
- only the chloroplast enzymee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Purified hexosediphosphatase prepared according to Racker and Schroeder and Buchanan et al. contained only the chloroplast enzyme.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
Claim · model-written summary
Both spinach enzymes specifically hydrolyse fructose 1,6-bisphosphate to fructose 6-phosphate and inorganic phosphate.
- Taxon
- SpinachSpinacia oleraceat0
- Gene
- enzymese0
- Outcome
- hydrolysis of fructose 1,6-bisphosphate to fructose 6-phosphate and inorganic phosphatee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Both enzymes catalyse specifically the hydrolysis of fructose 1,6-bisphosphate to fructose 6-phosphate and inorganic phosphate and show an absolute requirement for Mg2®.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
Claim · model-written summary
Both spinach enzymes absolutely require Mg2®.
- Taxon
- SpinachSpinacia oleraceat0
- Gene
- enzymese0
- Outcome
- absolute requirement for Mg2®e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Both enzymes catalyse specifically the hydrolysis of fructose 1,6-bisphosphate to fructose 6-phosphate and inorganic phosphate and show an absolute requirement for Mg2®.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
Claim · model-written summary
Mg2® concentration did not affect the cytoplasmic enzyme pH optimum.
- Taxon
- SpinachSpinacia oleraceat0
- Gene
- cytoplasmic enzymee0
- Compound
- Mg2®e0
- Outcome
- pH-optimum of the. cytoplasmic enzymee0
- Direction
- no effecte0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The concentration·, of Mg2® has no effect on the pH-optimum of the. cytoplasmic enzyme.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
Claim · model-written summary
The cytoplasmic enzyme had a lower pH optimum than the chloroplast enzyme, 7.5 versus 8.5.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- 10 mM Mg2®e0
- Outcome
- pH optimume0
- Direction
- lowere0
- Value
- 7.5e0
- Qualifier
- 8.5 for the chloroplast enzymee0
- Comparator
- chloroplast enzymee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“assayed with 10 mM Mg2® the pH optimum is lower, (7.5 for the cytoplasmic and 8.5 for the chloroplast enzyme) and the affinity for fructose bisphosphate at the pH optimum is greater.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
Claim · model-written summary
The cytoplasmic enzyme had greater affinity for fructose bisphosphate than the chloroplast enzyme.
- Taxon
- SpinachSpinacia oleraceat0
- Outcome
- affinity for fructose bisphosphatee0
- Direction
- greatere0
- Comparator
- chloroplast enzymee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“assayed with 10 mM Mg2® the pH optimum is lower, (7.5 for the cytoplasmic and 8.5 for the chloroplast enzyme) and the affinity for fructose bisphosphate at the pH optimum is greater.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
Claim · model-written summary
The cytoplasmic enzyme was not activated by dithiothreitol.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- dithiothreitole0
- Gene
- cytoplasmic enzymee0
- Outcome
- cytoplasmic enzymee0
- Direction
- not activatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the cytoplasmic enzyme is not activated by dithiothreitol or cystamine, but is inhibited by adenosine 5'-phosphate.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
Claim · model-written summary
The cytoplasmic enzyme was not activated by cystamine.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- cystaminee0
- Gene
- cytoplasmic enzymee0
- Outcome
- cytoplasmic enzymee0
- Direction
- not activatede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the cytoplasmic enzyme is not activated by dithiothreitol or cystamine, but is inhibited by adenosine 5'-phosphate.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
Claim · model-written summary
Adenosine 5'-phosphate inhibited the cytoplasmic enzyme.
- Taxon
- SpinachSpinacia oleraceat0
- Treatment
- adenosine 5'-phosphatee0
- Gene
- cytoplasmic enzymee0
- Outcome
- cytoplasmic enzymee0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the cytoplasmic enzyme is not activated by dithiothreitol or cystamine, but is inhibited by adenosine 5'-phosphate.”
t0“Evidence for a Hexosediphosphatase from the Cytoplasm of Spinach Leaves”
The same questions in other papers
cystamine · physiology: enzyme activity · Spinacia oleracea (spinach)Positive and negative results
1 in the opposite direction
- positive
1,4-dithiothreitol · physiology: enzyme activity · Spinacia oleracea (spinach)Results agree
3 papers in the same direction as this paper
- no effect
- no effect
- no effect
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.