Abstract
Upon addition of divalent cations to the incubation medium of cultured tobacco cells, the release of phosphatase into the medium increased and the time course of the release became biphasic. A rapid release (phase I release) occurred instantaneously after the addition and then a release at a constant rate (phase II release) followed. Sodium and potassium ions did not affect the enzyme release. Lanthanum ions caused the biphasic enzyme release but inhibited the phase II release. The effects of temperature and metabolic inhibitors indicated that phase I release was limited by a diffusion process but phase II release was limited by an enzymatic reaction requiring metabolic energy. From the results it was concluded that divalent cations enhanced the enzyme release not only by stimulating the transport of enzyme to the outside of the cell membrane, but also by liberating the enzyme retained on the exterior of the cells, e.g., the cell walls. The released phosphatase could be separated into two fractions, F-I and F-II. Only F-I was released by phase I release, while both F-I and F-II resulted from phase II release. This indicated that F-I was preferentially trapped on the exterior of the cells.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 12
Claim · model-written summary
Divalent cations increased phosphatase release and made its time course biphasic.
- Taxon
- tobacco cells
Nicotiana tabacume0 - Treatment
- addition of divalent cationse0
- Outcome
- release of phosphatasee0
- Direction
- increasede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Upon addition of divalent cations to the incubation medium of cultured tobacco cells, the release of phosphatase into the medium increased and the time course of the release became biphasic”
Claim · model-written summary
Phase I release occurred instantaneously and phase II followed at a constant rate.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Outcome
- release (phase I release)e0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A rapid release (phase I release) occurred instantaneously after the addition and then a release at a constant rate (phase II release) followed”
t0“tobacco cells”
Claim · model-written summary
Sodium and potassium ions did not affect enzyme release.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Treatment
- Sodium and potassium ionse0
- Outcome
- enzyme releasee0
- Direction
- did not affecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Sodium and potassium ions did not affect the enzyme release”
t0“tobacco cells”
Claim · model-written summary
Lanthanum ions caused biphasic release but inhibited phase II.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Treatment
- Lanthanum ionse0
- Outcome
- phase II releasee0
- Direction
- inhibitede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Lanthanum ions caused the biphasic enzyme release but inhibited the phase II release”
t0“tobacco cells”
Claim · model-written summary
Phase I release was limited by diffusion.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Outcome
- phase I releasee0
- Qualifier
- a diffusion processe0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“phase I release was limited by a diffusion process”
t0“tobacco cells”
Claim · model-written summary
Phase II release was limited by an energy-requiring enzymatic reaction.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Outcome
- phase II releasee0
- Qualifier
- an enzymatic reaction requiring metabolic energye0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“phase II release was limited by an enzymatic reaction requiring metabolic energy”
t0“tobacco cells”
Claim · model-written summary
Divalent cations were interpreted to stimulate phosphatase transport across the cell membrane.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Treatment
- divalent cationse0
- Outcome
- enzyme releasee0
- Direction
- enhancede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“divalent cations enhanced the enzyme release not only by stimulating the transport of enzyme to the outside of the cell membrane”
t0“tobacco cells”
Claim · model-written summary
Divalent cations were also interpreted to liberate phosphatase retained on cell exteriors.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Outcome
- enzyme retained on the exterior of the cellse0
- Qualifier
- liberatinge0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“but also by liberating the enzyme retained on the exterior of the cells, e.g., the cell walls”
t0“tobacco cells”
Claim · model-written summary
Released phosphatase separated into F-I and F-II fractions.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Outcome
- two fractions, F-I and F-IIe0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The released phosphatase could be separated into two fractions, F-I and F-II”
t0“tobacco cells”
Claim · model-written summary
Phase I released only F-I.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Outcome
- F-I was releasede0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Only F-I was released by phase I release”
t0“tobacco cells”
Claim · model-written summary
Phase II released both F-I and F-II.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Outcome
- both F-I and F-II resultede0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“both F-I and F-II resulted from phase II release”
t0“tobacco cells”
Claim · model-written summary
F-I was inferred to be preferentially trapped on cell exteriors.
- Taxon
- tobacco cellsNicotiana tabacumt0
- Outcome
- F-I was preferentially trappede0
- Qualifier
- on the exterior of the cellse0
Not reportedDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“F-I was preferentially trapped on the exterior of the cells”
t0“tobacco cells”
The same questions in other papers
potassium · physiology: enzyme activity · Nicotiana tabacum (tobacco)Positive and negative results
3 papers in the same direction as this paper · 2 in the opposite direction
- positive
- positive
- negative
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.