Abstract
Spinach plants grown without molybdenum lack nitrate reductase and when plants are deprived of nitrate existing activity is lost. Transfer of molybdenum-deficient plants to a solution containing (NH4)299MoO4) or nitrate-starved plants to NaNO3 solution induced enzyme activity in 24 hr. After purification by selective adsorption, precipitation and disc electrophoresis, the protein from molybdenum-deficient plants given 99Mo showed radioactivity only where nitrate reductase was revealed on the acrylamide gel. Molybdenum was similarly selectively concentrated into the enzyme as a result of induction by nitrate in plants grown with sub-optimal molybdenum supply in order to minimize effects of isotope dilution on measurement of 99Mo incorporation. There was no exchange in vitro between 99Mo and purified active enzyme in the resting state over 18 hr at 4°C, or with functioning enzyme held at room temperature for 24 hr. There was evidence either for possible in vivo exchange of 99Mo andenzyme bound Mo or for slight synthesis of fresh enzyme under conditions of net loss of enzyme in nitrate starved plants. Five NADH2 and two NADPH2 reactive diaphorases which could be separated by electrophoresis were present in extracts. Only one of these having strong NADH2 and weak NADPH2 activity was directly associated with nitrate reductase. The same complex also showed the only benzyl viologen (BV.) reactive nitrate reductase. Nitrate reductase in spinach is therefore considered to be a molybdenum-dependant and molybdenum-containing protein in which NADH2 (with weak NADPH2) and BVelectron donor functions and diaphorase/reductase activities remain closely associated during purification and electrophoresis. The techniques provide a simple means for the production and purification of enzyme containing radioactively labelled Mo applicable to investigations on the structure of the enzyme.
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Claims 12
Claim · model-written summary
Spinach grown without molybdenum lacks nitrate reductase.
- Taxon
- spinach
Spinacia oleraceat0 - Treatment
- grown without molybdenume1
- Gene
- nitrate reductasee1
- Outcome
- lack nitrate reductasee1
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e1“Spinach plants grown without molybdenum lack nitrate reductase and when plants are deprived of nitrate existing activity is lost”
Claim · model-written summary
Transfer of molybdenum-deficient spinach to a molybdenum solution induced enzyme activity within 24 hr.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- Transfer of molybdenum-deficient plants to a solution containing (NH4)299MoO4)e2
- Outcome
- enzyme activitye2
- Direction
- inducede2
- Qualifier
- in 24 hre2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e2“Transfer of molybdenum-deficient plants to a solution containing (NH4)299MoO4) or nitrate-starved plants to NaNO3 solution induced enzyme activity in 24 hr”
Claim · model-written summary
Transfer of nitrate-starved spinach to NaNO3 solution induced enzyme activity within 24 hr.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- nitrate-starved plants to NaNO3 solutione2
- Outcome
- enzyme activitye2
- Direction
- inducede2
- Qualifier
- in 24 hre2
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e2“Transfer of molybdenum-deficient plants to a solution containing (NH4)299MoO4) or nitrate-starved plants to NaNO3 solution induced enzyme activity in 24 hr”
Claim · model-written summary
The protein from molybdenum-deficient spinach given 99Mo showed radioactivity only where nitrate reductase was revealed on the gel.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- given 99Moe3
- Gene
- nitrate reductasee3
- Outcome
- radioactivitye3
- Qualifier
- only where nitrate reductase was revealed on the acrylamide gele3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e3“the protein from molybdenum-deficient plants given 99Mo showed radioactivity only where nitrate reductase was revealed on the acrylamide gel”
Claim · model-written summary
Molybdenum was selectively concentrated into the enzyme of spinach as a result of nitrate induction.
- Taxon
- spinachSpinacia oleraceat0
- Treatment
- induction by nitratee4
- Outcome
- Molybdenume4
- Direction
- selectively concentratede4
- Qualifier
- in plants grown with sub-optimal molybdenum supplye4
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e4“Molybdenum was similarly selectively concentrated into the enzyme as a result of induction by nitrate in plants grown with sub-optimal molybdenum supply in order to minimize effects of isotope dilution on measurement of 99Mo incorporation”
Claim · model-written summary
No exchange in vitro occurred between 99Mo and purified active spinach enzyme in the resting state over 18 hr at 4°C.
- Taxon
- spinachSpinacia oleraceat0
- Outcome
- exchange in vitro between 99Mo and purified active enzymee5
- Qualifier
- in the resting state over 18 hr at 4°Ce5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e5“There was no exchange in vitro between 99Mo and purified active enzyme in the resting state over 18 hr at 4°C, or with functioning enzyme held at room temperature for 24 hr”
Claim · model-written summary
There was evidence for possible in vivo exchange of 99Mo with enzyme-bound Mo in spinach, or for slight synthesis of fresh enzyme under net loss.
- Taxon
- spinachSpinacia oleraceat0
- Outcome
- possible in vivo exchangee6
- Qualifier
- or for slight synthesis of fresh enzyme under conditions of net loss of enzyme in nitrate starved plantse6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e6“There was evidence either for possible in vivo exchange of 99Mo andenzyme bound Mo or for slight synthesis of fresh enzyme under conditions of net loss of enzyme in nitrate starved plants”
Claim · model-written summary
Five NADH2-reactive and two NADPH2-reactive diaphorases were present in spinach extracts and could be separated by electrophoresis.
- Taxon
- spinachSpinacia oleraceat0
- Outcome
- reactive diaphorasese7
- Value
- Five NADH2 and two NADPH2e7
- Qualifier
- which could be separated by electrophoresise7
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e7“Five NADH2 and two NADPH2 reactive diaphorases which could be separated by electrophoresis were present in extracts”
Claim · model-written summary
Only one spinach diaphorase, with strong NADH2 and weak NADPH2 activity, was directly associated with nitrate reductase.
- Taxon
- spinachSpinacia oleraceat0
- Gene
- nitrate reductasee1
- Outcome
- directly associated with nitrate reductasee1
- Qualifier
- having strong NADH2 and weak NADPH2 activitye1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e1“Only one of these having strong NADH2 and weak NADPH2 activity was directly associated with nitrate reductase”
Claim · model-written summary
The same spinach diaphorase complex showed the only benzyl viologen (BV.) reactive nitrate reductase.
- Taxon
- spinachSpinacia oleraceat0
- Gene
- nitrate reductasee2
- Outcome
- benzyl viologen (BV.) reactive nitrate reductasee2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e2“The same complex also showed the only benzyl viologen (BV.) reactive nitrate reductase”
Claim · model-written summary
Spinach nitrate reductase is considered a molybdenum-dependent and molybdenum-containing protein.
- Taxon
- spinachSpinacia oleraceat0
- Outcome
- molybdenum-dependant and molybdenum-containing proteine3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“spinach (Spinacea oleracea L.)”
e3“Nitrate reductase in spinach is therefore considered to be a molybdenum-dependant and molybdenum-containing protein in which NADH2 (with weak NADPH2) and BVelectron donor functions and diaphorase/reductase activities remain closely associated during purification and electrophoresis”
Claim · model-written summary
The techniques give a simple means for producing and purifying radioactively labelled Mo enzyme for structure studies.
- Outcome
- production and purification of enzyme containing radioactively labelled Moe4
Not reportedComparator
Verbatim
e4“The techniques provide a simple means for the production and purification of enzyme containing radioactively labelled Mo applicable to investigations on the structure of the enzyme”
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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.