Abstract
Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano). The isozymes were separated by affinity chromatography on Heparin-Sepharose column. They exhibited a molecular mass of 31 kDa when analyzed in sodium dodecyl sulfate gel electrophoresis and of 35 kDa in gel-filtration chromatography in native conditions. The isoelectric points of all three isozymes were found to be higher than 9.3. The Kms calculated for the three isozymes were different toward citrus pectin used as substrate; one had a Km of 9.7 mM (by expressing the pectin concentration as mmoles/L of methoxy groups) and the other two had similar Kms of 3.0 and 2.6 mM, respectively. The isozyme having the higher Km for substrate was inhibited by citrus pectin (which had a degree of methylation of 70%) at concentrations higher than 5 mM, but no inhibition was found using a pectin with a degree of methylation of 30% at concentrations up to 13 mM (i.e. 9 mg/ml) with a Km of 14.7 mM. Furthermore, this isozyme showed a more broad range of activity in a pH range 5–10 with respect to that exhibited by the other two isozymes. All three isozymes were found to be glycosylated, although to different extents.
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Claims 9
Claim · model-written summary
The pectin methylesterase isozymes of tomato showed a molecular mass of 31 kDa by SDS gel electrophoresis.
- Taxon
- tomato
Solanum lycopersicume0 - Gene
- pectin methylesterasee0
- Outcome
- molecular masse1
- Value
- 31 kDae1
- Qualifier
- sodium dodecyl sulfate gel electrophoresise1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e1“They exhibited a molecular mass of 31 kDa when analyzed in sodium dodecyl sulfate gel electrophoresis and of 35 kDa in gel-filtration chromatography in native conditions”
Claim · model-written summary
The pectin methylesterase isozymes of tomato showed a molecular mass of 35 kDa by gel-filtration chromatography in native conditions.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- pectin methylesterasee0
- Outcome
- molecular masse1
- Value
- 35 kDae1
- Qualifier
- gel-filtration chromatography in native conditionse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e1“They exhibited a molecular mass of 31 kDa when analyzed in sodium dodecyl sulfate gel electrophoresis and of 35 kDa in gel-filtration chromatography in native conditions”
Claim · model-written summary
The isoelectric points of all three isozymes were higher than 9.3.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- pectin methylesterasee0
- Outcome
- isoelectric pointse2
- Value
- higher than 9.3e2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e2“The isoelectric points of all three isozymes were found to be higher than 9.3”
Claim · model-written summary
The isozyme with the higher Km had a Km of 9.7 mM toward citrus pectin.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- pectin methylesterasee0
- Outcome
- Kme3
- Value
- 9.7 mMe3
- Qualifier
- expressing the pectin concentration as mmoles/L of methoxy groupse3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e3“The Kms calculated for the three isozymes were different toward citrus pectin used as substrate; one had a Km of 9.7 mM (by expressing the pectin concentration as mmoles/L of methoxy groups) and the other two had similar Kms of 3.0 and 2.6 mM, respectively”
Claim · model-written summary
The other two isozymes had similar Km values of 3.0 and 2.6 mM toward citrus pectin.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- pectin methylesterasee0
- Outcome
- Kme3
- Value
- 3.0 and 2.6 mMe3
- Qualifier
- similare3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e3“The Kms calculated for the three isozymes were different toward citrus pectin used as substrate; one had a Km of 9.7 mM (by expressing the pectin concentration as mmoles/L of methoxy groups) and the other two had similar Kms of 3.0 and 2.6 mM, respectively”
Claim · model-written summary
Citrus pectin with a degree of methylation of 70% inhibited the high-Km isozyme at concentrations above 5 mM.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- citrus pectine4
- Gene
- pectin methylesterasee0
- Outcome
- inhibitione4
- Qualifier
- at concentrations higher than 5 mMe4
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e4“The isozyme having the higher Km for substrate was inhibited by citrus pectin (which had a degree of methylation of 70%) at concentrations higher than 5 mM, but no inhibition was found using a pectin with a degree of methylation of 30% at concentrations up to 13 mM”
Claim · model-written summary
Pectin with a degree of methylation of 30% did not inhibit the high-Km isozyme at concentrations up to 13 mM.
- Taxon
- tomatoSolanum lycopersicume0
- Treatment
- a pectin with a degree of methylation of 30%e4
- Gene
- pectin methylesterasee0
- Outcome
- inhibitione4
- Qualifier
- at concentrations up to 13 mMe4
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e4“The isozyme having the higher Km for substrate was inhibited by citrus pectin (which had a degree of methylation of 70%) at concentrations higher than 5 mM, but no inhibition was found using a pectin with a degree of methylation of 30% at concentrations up to 13 mM”
Claim · model-written summary
The high-Km isozyme showed a broader pH range of activity (pH 5-10) than the other two isozymes.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- pectin methylesterasee0
- Outcome
- range of activitye5
- Direction
- more broade5
- Value
- pH range 5–10e5
- Comparator
- the other two isozymese5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e5“this isozyme showed a more broad range of activity in a pH range 5–10 with respect to that exhibited by the other two isozymes”
Claim · model-written summary
All three isozymes were glycosylated, to different extents.
- Taxon
- tomatoSolanum lycopersicume0
- Gene
- pectin methylesterasee0
- Outcome
- glycosylatede6
- Qualifier
- to different extentse6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Three isozymes of pectin methylesterase (EC 3.1.1.11) have been purified to homogeneity from tomato (var. S. marzano)”
e6“All three isozymes were found to be glycosylated, although to different extents”
The same questions in other papers
pectin · disease · Solanum lycopersicum (tomato)Positive and negative results
2 papers in the same direction as this paper · 3 in the opposite direction
- positive
- positive
- positive
2 papers more in this group
See all 6 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.