Abstract
Abstract To understand why riboflavin is excreted by tobacco and some other Fe‐efficient dicotyledonous species under Fe stress, normal and Fe‐deficient tobacco were assayed for ferredoxin and flavodoxin, a ferredoxin replacement electron transpon molecule produced in some Fe‐stressed bacteria and algae. Decreases in leaf ferredoxin corresponded to decreases in leaf chlorophyll content. Activity of purified ferredoxin from Fe‐stressed leaves was slightly less than that from normal leaves. No flavodoxin could be detected in extracts from Fe‐stressed or normal tobacco leaves or roots, although abundant riboflavin was present in the Fe‐stressed tissues. Flavodoxin was isolated and purified from Clostridium oasteurianum and the antiserum prepared from this did not react with a likely protein from Fe‐stressed leaves, nor did it exhibit other properties of flavodoxin. A ferredoxin‐like protein was purified from roots of normal but not Fe‐stressed tobacco. It reacted with anti serum prepared from purified tobacco leaf ferredoxin and had the same mobility with SDS‐PAGE. It functioned when chemically reduced as an electron transpor. agent in a nitrite reductase catalyzed reduction of nitrite, but could not function in NADP+ reduction by illuminated chloroplasts as did ferredoxin. A possible in vivo role for increased riboflavin or FMN in Fe‐stressed tissue should still be considered.
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Claims 8
Claim · model-written summary
Decreases in leaf ferredoxin corresponded to decreases in leaf chlorophyll content in tobacco.
- Taxon
- tobacco
Nicotiana tabacumt0 - Organ / stage
- leafe1
- Gene
- ferredoxine1
- Outcome
- leaf ferredoxine1
- Direction
- Decreasese1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ferredoxin and flavodoxin analysis in tobacco in response to iron stress”
e1“Decreases in leaf ferredoxin corresponded to decreases in leaf chlorophyll content”
Claim · model-written summary
Activity of purified ferredoxin from Fe-stressed tobacco leaves was slightly less than from normal leaves.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- leavese2
- Treatment
- Fe‐stressede2
- Gene
- ferredoxine2
- Outcome
- Activity of purified ferredoxine2
- Direction
- slightly lesse2
- Comparator
- normal leavese2
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ferredoxin and flavodoxin analysis in tobacco in response to iron stress”
e2“Activity of purified ferredoxin from Fe‐stressed leaves was slightly less than that from normal leaves”
Claim · model-written summary
No flavodoxin could be detected in tobacco leaves or roots, normal or Fe-stressed.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- leaves or rootse3
- Gene
- flavodoxine3
- Outcome
- flavodoxine3
- Qualifier
- No flavodoxin could be detected in extracts from Fe‐stressed or normal tobacco leaves or rootse3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ferredoxin and flavodoxin analysis in tobacco in response to iron stress”
e3“No flavodoxin could be detected in extracts from Fe‐stressed or normal tobacco leaves or roots, although abundant riboflavin was present in the Fe‐stressed tissues”
Claim · model-written summary
Riboflavin was abundant in Fe-stressed tobacco tissues.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- tissuese3
- Outcome
- riboflavine3
- Qualifier
- abundant riboflavin was present in the Fe‐stressed tissuese3
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ferredoxin and flavodoxin analysis in tobacco in response to iron stress”
e3“No flavodoxin could be detected in extracts from Fe‐stressed or normal tobacco leaves or roots, although abundant riboflavin was present in the Fe‐stressed tissues”
Claim · model-written summary
A ferredoxin-like protein was purified from roots of normal but not Fe-stressed tobacco.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- rootse4
- Gene
- ferredoxin‐like proteine4
- Outcome
- ferredoxin‐like proteine4
- Qualifier
- normal but not Fe‐stressede4
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ferredoxin and flavodoxin analysis in tobacco in response to iron stress”
e4“A ferredoxin‐like protein was purified from roots of normal but not Fe‐stressed tobacco”
Claim · model-written summary
The ferredoxin-like protein of tobacco reacted with antiserum to leaf ferredoxin and had the same mobility in SDS-PAGE.
- Taxon
- tobaccoNicotiana tabacumt0
- Organ / stage
- leafe5
- Outcome
- reacted with anti serume5
- Qualifier
- had the same mobility with SDS‐PAGEe5
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ferredoxin and flavodoxin analysis in tobacco in response to iron stress”
e5“It reacted with anti serum prepared from purified tobacco leaf ferredoxin and had the same mobility with SDS‐PAGE”
Claim · model-written summary
The ferredoxin-like protein of tobacco functioned as an electron transport agent in nitrite reduction when chemically reduced.
- Taxon
- tobaccoNicotiana tabacumt0
- Outcome
- reduction of nitritee6
- Qualifier
- functioned when chemically reduced as an electron transpor. agente6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ferredoxin and flavodoxin analysis in tobacco in response to iron stress”
e6“It functioned when chemically reduced as an electron transpor. agent in a nitrite reductase catalyzed reduction of nitrite, but could not function in NADP+ reduction by illuminated chloroplasts as did ferredoxin”
Claim · model-written summary
The ferredoxin-like protein of tobacco could not function in NADP+ reduction by illuminated chloroplasts.
- Taxon
- tobaccoNicotiana tabacumt0
- Outcome
- NADP+ reduction by illuminated chloroplastse6
- Qualifier
- could not functione6
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
t0“Ferredoxin and flavodoxin analysis in tobacco in response to iron stress”
e6“It functioned when chemically reduced as an electron transpor. agent in a nitrite reductase catalyzed reduction of nitrite, but could not function in NADP+ reduction by illuminated chloroplasts as did ferredoxin”
The same questions in other papers
iron atom · molecular: metabolites · Nicotiana tabacum (tobacco)Positive and negative results
2 papers in the same direction as this paper · 2 in the opposite direction
- positive
- positive
- no effect
1 paper more in this group
See all 5 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.