Abstract
Spinach chloroplasts were incubated in the dark with methyl acetimidate in order to amidinate and thereby protect free amino groups. An energy-dependent attack on the coupling factor (CF1) of these amidinated chloroplasts by trinitrobenzenesulfonate was apparent in a second reaction, as long as the reagent was applied in the light or after an acid-base transition. Trinitrophenyl residues approached one each on the alpha and beta subunits, and two to three on the gamma subunit polypeptide of CF1. Accompanying trinitrophenylation was an inhibition of the ATPase activity of CF1 due to a major decrease in the affinity for ATP; however, neither the maximal ATPase rate nor the ability of the protein to serve as a coupling factor for EDTA-extracted chloroplasts was affected. Trinitrophenylation and consequent inhibition of ATPase were 50% prevented by the presence of phosphate, or ADP, or ATP during exposure to trinitrobenzenesulfonate. The protective effects of adenylates were additive with those of phosphate. The ratio of trinitrophenyl groups on the three subunits concerned was the same whether phosphate or ATP was providing 50% protection, or whether neither was present. It is inferred that a conformational change occurs in the amidinated coupling factor when a proton activity gradient is placed across the membranes, and effective ligands tend to prevent the resulting exposure of free amino groups from a previously hidden location.
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Claims 13
Claim · model-written summary
An energy-dependent attack on CF1 by trinitrobenzenesulfonate occurred when the reagent was applied in the light or after an acid-base transition.
- Taxon
- spinach
Spinacia oleraceat0 - Treatment
- trinitrobenzenesulfonatee1
- Gene
- coupling factor (CF1)e1
- Outcome
- energy-dependent attack on the coupling factor (CF1)e1
- Qualifier
- as long as the reagent was applied in the light or after an acid-base transitione1
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e1“An energy-dependent attack on the coupling factor (CF1) of these amidinated chloroplasts by trinitrobenzenesulfonate was apparent in a second reaction, as long as the reagent was applied in the light or after an acid-base transition”
Claim · model-written summary
Trinitrophenyl residues approached one each on the alpha and beta subunits of CF1.
- Taxon
- spinachSpinacia oleraceat0
- Gene
- alpha and beta subunitse2
- Outcome
- Trinitrophenyl residuese2
- Value
- one eache2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e2“Trinitrophenyl residues approached one each on the alpha and beta subunits”
Claim · model-written summary
Trinitrophenyl residues were two to three on the gamma subunit polypeptide of CF1.
- Taxon
- spinachSpinacia oleraceat0
- Gene
- gamma subunit polypeptide of CF1e3
- Outcome
- Trinitrophenyl residuese3
- Value
- two to threee3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e3“Trinitrophenyl residues approached one each on the alpha and beta subunits, and two to three on the gamma subunit polypeptide of CF1”
Claim · model-written summary
Trinitrophenylation inhibited the ATPase activity of CF1.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- trinitrophenylatione4
- Outcome
- ATPase activity of CF1e4
- Direction
- decreaseinferrede4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e4“Accompanying trinitrophenylation was an inhibition of the ATPase activity of CF1”
Claim · model-written summary
The inhibition of CF1 ATPase activity by trinitrophenylation is attributed to a major decrease in the affinity for ATP.
- Taxon
- spinachSpinacia oleraceat0
- Outcome
- affinity for ATPe5
- Qualifier
- major decrease in the affinity for ATPe5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e5“due to a major decrease in the affinity for ATP”
Claim · model-written summary
Trinitrophenylation did not change the maximal ATPase rate of CF1.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- trinitrophenylatione3
- Outcome
- maximal ATPase ratee3
- Direction
- no_changeinferrede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e3“Accompanying trinitrophenylation was an inhibition of the ATPase activity of CF1 due to a major decrease in the affinity for ATP; however, neither the maximal ATPase rate nor the ability of the protein to serve as a coupling factor for EDTA-extracted chloroplasts was affected”
Claim · model-written summary
Trinitrophenylation did not change the ability of CF1 to serve as a coupling factor for EDTA-extracted chloroplasts.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- trinitrophenylatione3
- Outcome
- ability of the protein to serve as a coupling factore3
- Direction
- no_changeinferrede3
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e3“Accompanying trinitrophenylation was an inhibition of the ATPase activity of CF1 due to a major decrease in the affinity for ATP; however, neither the maximal ATPase rate nor the ability of the protein to serve as a coupling factor for EDTA-extracted chloroplasts was affected”
Claim · model-written summary
Phosphate prevented 50% of trinitrophenylation and consequent ATPase inhibition.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- phosphatee4
- Outcome
- Trinitrophenylation and consequent inhibition of ATPasee4
- Direction
- decreaseinferrede4
- Value
- 50%e4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e4“Trinitrophenylation and consequent inhibition of ATPase were 50% prevented by the presence of phosphate, or ADP, or ATP during exposure to trinitrobenzenesulfonate”
Claim · model-written summary
ADP prevented 50% of trinitrophenylation and consequent ATPase inhibition.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- ADPe4
- Outcome
- Trinitrophenylation and consequent inhibition of ATPasee4
- Direction
- decreaseinferrede4
- Value
- 50%e4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e4“Trinitrophenylation and consequent inhibition of ATPase were 50% prevented by the presence of phosphate, or ADP, or ATP during exposure to trinitrobenzenesulfonate”
Claim · model-written summary
ATP prevented 50% of trinitrophenylation and consequent ATPase inhibition.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- ATPe4
- Outcome
- Trinitrophenylation and consequent inhibition of ATPasee4
- Direction
- decreaseinferrede4
- Value
- 50%e4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e4“Trinitrophenylation and consequent inhibition of ATPase were 50% prevented by the presence of phosphate, or ADP, or ATP during exposure to trinitrobenzenesulfonate”
Claim · model-written summary
The protective effects of adenylates were additive with those of phosphate.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- adenylatese5
- Outcome
- protective effects of adenylatese5
- Qualifier
- additivee5
- Comparator
- those of phosphatee5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e5“The protective effects of adenylates were additive with those of phosphate”
Claim · model-written summary
The ratio of trinitrophenyl groups on the three subunits of CF1 was the same with phosphate or ATP protection and without protection.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- phosphate or ATPe6
- Outcome
- ratio of trinitrophenyl groups on the three subunitse6
- Direction
- the samee6
- Comparator
- neither was presente6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e6“The ratio of trinitrophenyl groups on the three subunits concerned was the same whether phosphate or ATP was providing 50% protection, or whether neither was present”
Claim · model-written summary
A conformational change in the amidinated coupling factor is inferred to expose free amino groups when a proton gradient is applied across the membranes.
- Taxon
- spinachSpinacia oleraceat0
- Outcome
- exposure of free amino groupse7
- Qualifier
- conformational change occurs in the amidinated coupling factor when a proton activity gradient is placed across the membranese7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“energized spinach chloroplasts”
e7“It is inferred that a conformational change occurs in the amidinated coupling factor when a proton activity gradient is placed across the membranes, and effective ligands tend to prevent the resulting exposure of free amino groups from a previously hidden location”
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3 papers more in this group
See all 7 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.