Abstract
The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach. A combination of oxygen evolution, chlorophyll fluorescence induction (FI) and decay and thermoluminescence measurements have been used to characterize photosystem II (PSII) electron transport in the presence of this toxic metal cation. Our results show that below 3 mm, Al(3+) already caused a destabilization of the Mn4 O5 Ca cluster of the oxygen evolving complex (OEC). At these concentrations, an increase in the relative amplitude of the first phase (OJ) of FI curve and retardation of the fluorescence decay kinetics following excitation with a single turnover flash were also observed. A transmembrane structural modification of PSII polypeptides due to the interaction of Al(3+) at the OEC is proposed to retard electron transfer between the quinones QA and QB . Above 3 mm, Al(3+) strongly retarded fluorescence induction and significantly reduced Fv /Fm together with the maximal amplitude of chlorophyll fluorescence induced by a single turnover flash. This chlorophyll fluorescence quenching was attributed to the formation of P680(+) due to inhibition of electron transfer between tyrosine 161 of D1 subunit and P680.
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Claims 8
Claim · model-written summary
Al(3+) below 3 mm destabilized the Mn4 O5 Ca cluster of the oxygen evolving complex in spinach.
- Taxon
- spinach
Spinacia oleraceae1 - Treatment
- Al(3+)e0
- Outcome
- destabilization of the Mn4 O5 Ca clustere0
- Direction
- destabilizatione0
- Qualifier
- below 3 mme0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Our results show that below 3 mm, Al(3+) already caused a destabilization of the Mn4 O5 Ca cluster of the oxygen evolving complex (OEC).”
e1“The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach.”
Claim · model-written summary
At concentrations below 3 mm, Al(3+) increased the OJ phase amplitude.
- Taxon
- spinachSpinacia oleraceae1
- Treatment
- Al(3+)e1
- Outcome
- relative amplitude of the first phase (OJ) of FI curvee0
- Direction
- increasee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At these concentrations, an increase in the relative amplitude of the first phase (OJ) of FI curve and retardation of the fluorescence decay kinetics following excitation with a single turnover flash were also observed.”
e1“The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach.”
Claim · model-written summary
At these Al(3+) concentrations, fluorescence decay was retarded.
- Taxon
- spinachSpinacia oleraceae1
- Treatment
- Al(3+)e1
- Outcome
- fluorescence decay kineticse0
- Direction
- retardatione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“At these concentrations, an increase in the relative amplitude of the first phase (OJ) of FI curve and retardation of the fluorescence decay kinetics following excitation with a single turnover flash were also observed.”
e1“The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach.”
Claim · model-written summary
Above 3 mm Al(3+) retarded fluorescence induction in spinach.
- Taxon
- spinachSpinacia oleraceae1
- Treatment
- Al(3+)e0
- Outcome
- fluorescence inductione0
- Direction
- retardede0
- Qualifier
- Above 3 mme0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Above 3 mm, Al(3+) strongly retarded fluorescence induction and significantly reduced Fv /Fm together with the maximal amplitude of chlorophyll fluorescence induced by a single turnover flash.”
e1“The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach.”
Claim · model-written summary
Above 3 mm Al(3+) reduced Fv /Fm in spinach.
- Taxon
- spinachSpinacia oleraceae1
- Treatment
- Al(3+)e0
- Outcome
- Fv /Fme0
- Direction
- reducede0
- Qualifier
- Above 3 mme0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Above 3 mm, Al(3+) strongly retarded fluorescence induction and significantly reduced Fv /Fm together with the maximal amplitude of chlorophyll fluorescence induced by a single turnover flash.”
e1“The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach.”
Claim · model-written summary
Above 3 mm Al(3+) reduced maximal amplitude of chlorophyll fluorescence in spinach.
- Taxon
- spinachSpinacia oleraceae1
- Treatment
- Al(3+)e0
- Outcome
- maximal amplitude of chlorophyll fluorescencee0
- Direction
- reducede0
- Qualifier
- Above 3 mme0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Above 3 mm, Al(3+) strongly retarded fluorescence induction and significantly reduced Fv /Fm together with the maximal amplitude of chlorophyll fluorescence induced by a single turnover flash.”
e1“The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach.”
Claim · model-written summary
Al(3+) interaction at the oxygen evolving complex was proposed to alter PSII structure and retard electron transfer.
- Taxon
- spinachSpinacia oleraceae1
- Treatment
- Al(3+)e0
- Outcome
- retard electron transfer between the quinones QA and QBe0
- Qualifier
- transmembrane structural modification of PSII polypeptidese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“A transmembrane structural modification of PSII polypeptides due to the interaction of Al(3+) at the OEC is proposed to retard electron transfer between the quinones QA and QB .”
e1“The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach.”
Claim · model-written summary
Fluorescence quenching was attributed to P680(+) formation following inhibited electron transfer.
- Taxon
- spinachSpinacia oleraceae1
- Outcome
- chlorophyll fluorescence quenchinge0
- Qualifier
- formation of P680(+) due to inhibition of electron transfer between tyrosine 161 of D1 subunit and P680e0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“This chlorophyll fluorescence quenching was attributed to the formation of P680(+) due to inhibition of electron transfer between tyrosine 161 of D1 subunit and P680.”
e1“The inhibitory effect of Al(3+) on photosynthetic electron transport was investigated in isolated thylakoid membranes of spinach.”
The same questions in other papers
aluminium atom · molecular: metabolites · Spinacia oleracea (spinach)Positive and negative results
1 paper in the same direction as this paper · 1 in the opposite direction
- negative
- positive
aluminium atom · physiology: photosynthesis · Spinacia oleracea (spinach)Results agree
1 paper in the same direction as this paper
- negative
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.