Abstract
Fructose 2,6-bisphosphate (F 2,6-P(2)) was detected in the CAM species, Ananas comosus and Bryophyllum tubiflorum, and in C(3)- and CAM-Mesembryanthemum crystallinum. In both Mesembryanthemum tissues, F 2,6-P(2) was located outside the chloroplast. The levels of F 2,6-P(2), malate, starch, or soluble sugars were measured during various periods during the day-night cycle in the leaves of Ananas, a species which stores carbohydrate in an extrachloroplastic compartment, and in Bryophyllum, a species which stores carbon as starch in the chloroplast. In both species, the levels of F 2,6-P(2) were correlated with the stages of the day-night CAM cycle. Immediately following the dark-light transition the F 2,6-P(2) levels exhibited a rapid transient increase followed by a decrease. F 2,6-P(2) reached a daily minimum soon after the onset of deacidification and remained low until the malic acid pools approached their daily minima; the levels of F 2,6-P(2) then began a slow increase which accelerated during the period of afternoon CO(2) uptake. Immediately following the light-dark transition F 2,6-P(2) levels fluctuated. The levels were usually low after the fluctuations had ceased. The pools then increased as the rate of malate synthesis increased, remained at relatively constant high levels when the rates of malate synthesis were constant, and decreased as malate synthesis decreased towards the end of the dark period. The absolute levels of F 2,6-P(2) were always higher in Ananas than in Bryophyllum. The ratios of the activity of pyrophosphate fructose-6-phosphate l-phosphotransferase to cytoplasmic fructose 1,6-bisphosphatase and to phosphofructokinase were also far higher in Ananas than in Bryophyllum or in C(3)- or CAM-Mesembryanthemum.
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Claims 13
Claim · model-written summary
Fructose 2,6-bisphosphate was detected in Ananas comosus.
- Taxon
- Ananas comosus
Ananas comosuse0 - Compound
- Fructose 2,6-bisphosphatee0
- Outcome
- detectede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fructose 2,6-bisphosphate (F 2,6-P(2)) was detected in the CAM species, Ananas comosus and Bryophyllum tubiflorum”
Claim · model-written summary
Fructose 2,6-bisphosphate was detected in Bryophyllum tubiflorum.
- Taxon
- Bryophyllum tubiflorum
_Kalanchoe_delagoensis_Eckl._%26_Zeyh._(1837).jpg?width=60)
Kalanchoe delagoensise0 - Compound
- Fructose 2,6-bisphosphatee0
- Outcome
- detectede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
_Kalanchoe_delagoensis_Eckl._%26_Zeyh._(1837).jpg?width=500)
Verbatim
e0“Fructose 2,6-bisphosphate (F 2,6-P(2)) was detected in the CAM species, Ananas comosus and Bryophyllum tubiflorum”
Claim · model-written summary
Fructose 2,6-bisphosphate was detected in C3 and CAM Mesembryanthemum crystallinum.
- Taxon
- Mesembryanthemum crystallinum
Mesembryanthemum crystallinume0 - Outcome
- CAM-Mesembryanthemum crystallinume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“and in C(3)- and CAM-Mesembryanthemum crystallinum.”
Claim · model-written summary
In both Mesembryanthemum tissues, F 2,6-P(2) was outside chloroplasts.
- Taxon
- Mesembryanthemum
Mesembryanthemume0 - Organ / stage
- chloroplaste0
- Compound
- F 2,6-P(2)e0
- Outcome
- located outside the chloroplaste0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In both Mesembryanthemum tissues, F 2,6-P(2) was located outside the chloroplast.”
Claim · model-written summary
F 2,6-P(2) levels correlated with stages of the day-night CAM cycle in both Ananas and Bryophyllum.
- Organ / stage
- stages of the day-night CAM cyclee0
- Compound
- F 2,6-P(2)e0
- Outcome
- levels of F 2,6-P(2)e0
- Direction
- correlatede0
AnanasOrganisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“In both species, the levels of F 2,6-P(2) were correlated with the stages of the day-night CAM cycle.”
e1“in the leaves of Ananas, a species which stores carbohydrate in an extrachloroplastic compartment”
Claim · model-written summary
F 2,6-P(2) rose rapidly then fell after dark-to-light transition.
- Compound
- F 2,6-P(2)e0
- Outcome
- F 2,6-P(2) levelse0
- Direction
- rapid transient increase followed by a decreasee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Immediately following the dark-light transition the F 2,6-P(2) levels exhibited a rapid transient increase followed by a decrease.”
e1“in the leaves of Ananas, a species which stores carbohydrate in an extrachloroplastic compartment”
Claim · model-written summary
F 2,6-P(2) reached a minimum after deacidification began and stayed low until malic acid approached its minimum.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“F 2,6-P(2) reached a daily minimum soon after the onset of deacidification and remained low until the malic acid pools approached their daily minima”
e1“in the leaves of Ananas, a species which stores carbohydrate in an extrachloroplastic compartment”
Claim · model-written summary
F 2,6-P(2) increased later, accelerating during afternoon carbon uptake.
- Compound
- F 2,6-P(2)e0
- Outcome
- levels of F 2,6-P(2)e0
- Direction
- slow increasee0
- Qualifier
- afternoon CO(2) uptakee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the levels of F 2,6-P(2) then began a slow increase which accelerated during the period of afternoon CO(2) uptake.”
e1“in the leaves of Ananas, a species which stores carbohydrate in an extrachloroplastic compartment”
Claim · model-written summary
After light-to-dark transition, F 2,6-P(2) fluctuated and then was usually low.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Immediately following the light-dark transition F 2,6-P(2) levels fluctuated. The levels were usually low after the fluctuations had ceased.”
e1“in the leaves of Ananas, a species which stores carbohydrate in an extrachloroplastic compartment”
Claim · model-written summary
F 2,6-P(2) pools rose with malate synthesis, stayed high when synthesis was constant, then fell as synthesis waned.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The pools then increased as the rate of malate synthesis increased, remained at relatively constant high levels when the rates of malate synthesis were constant, and decreased as malate synthesis decreased towards the end of the dark period.”
e1“in the leaves of Ananas, a species which stores carbohydrate in an extrachloroplastic compartment”
Claim · model-written summary
F 2,6-P(2) levels were always higher in Ananas than Bryophyllum.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The absolute levels of F 2,6-P(2) were always higher in Ananas than in Bryophyllum.”
Claim · model-written summary
The ratio of pyrophosphate fructose-6-phosphate phosphotransferase to cytoplasmic fructose 1,6-bisphosphatase activity was far higher in Ananas.
- Gene
- pyrophosphate fructose-6-phosphate l-phosphotransferasee0
- Outcome
- ratios of the activitye0
- Direction
- far highere0
- Comparator
- Bryophyllume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ratios of the activity of pyrophosphate fructose-6-phosphate l-phosphotransferase to cytoplasmic fructose 1,6-bisphosphatase and to phosphofructokinase were also far higher in Ananas than in Bryophyllum or in C(3)- or CAM-Mesembryanthemum.”
Claim · model-written summary
The ratio of pyrophosphate fructose-6-phosphate phosphotransferase to phosphofructokinase activity was far higher in Ananas.
- Gene
- phosphofructokinasee0
- Outcome
- ratios of the activitye0
- Direction
- far highere0
- Comparator
- Bryophyllume0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The ratios of the activity of pyrophosphate fructose-6-phosphate l-phosphotransferase to cytoplasmic fructose 1,6-bisphosphatase and to phosphofructokinase were also far higher in Ananas than in Bryophyllum or in C(3)- or CAM-Mesembryanthemum.”