Abstract
Bacterial lipoproteins play crucial roles in host-pathogen interactions and pathogenesis and are important targets for the immune system. A prominent example is the outer surface protein A (OspA) of Borrelia burgdorferi, which has been efficiently used as a vaccine for the prevention of Lyme disease. In a previous study, OspA could be produced in tobacco chloroplasts in a lipidated and immunogenic form. To further explore the potential of chloroplasts for the production of bacterial lipoproteins, the role of the N-terminal leader sequence was investigated. The amount of recombinant OspA could be increased up to ten-fold by the variation of the insertion site in the chloroplast genome. Analysis of OspA mutants revealed that replacement of the invariant cysteine residue as well as deletion of the leader sequence abolishes palmitolyation of OspA. Also, decoration of OspA with an N-terminal eukaryotic lipidation motif does not lead to palmitoylation in chloroplasts. Strikingly, the bacterial signal peptide of OspA efficiently targets the protein to thylakoids, and causes a mutant phenotype. Plants accumulating OspA at 10% total soluble protein could not grow without exogenously supplied sugars and rapidly died after transfer to soil under greenhouse conditions. The plants were found to be strongly affected in photosystem II, as revealed by the analyses of temporal and spatial dynamics of photosynthetic activity by chlorophyll fluorescence imaging. Thus, overexpression of OspA in chloroplasts is limited by its concentration-dependent interference with essential functions of chloroplastic membranes required for primary metabolism.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 8
Claim · model-written summary
Changing the chloroplast insertion site increased OspA amounts up to tenfold.
- Taxon
- tobacco
Nicotiana tabacumt0 - Treatment
- variation of the insertion sitee0
- Gene
- OspAe0
- Outcome
- amount of recombinant OspAe0
- Direction
- increasede0
- Value
- ten-folde0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The amount of recombinant OspA could be increased up to ten-fold by the variation of the insertion site in the chloroplast genome.”
t0“Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis”
Claim · model-written summary
Replacing the invariant cysteine abolished OspA palmitoylation.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- replacement of the invariant cysteine residuee0
- Gene
- OspAe0
- Outcome
- palmitolyation of OspAe0
- Direction
- abolishese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“replacement of the invariant cysteine residue as well as deletion of the leader sequence abolishes palmitolyation of OspA.”
t0“Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis”
Claim · model-written summary
Deleting the leader sequence abolished OspA palmitoylation.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- deletion of the leader sequencee0
- Gene
- OspAe0
- Outcome
- palmitolyation of OspAe0
- Direction
- abolishese0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“replacement of the invariant cysteine residue as well as deletion of the leader sequence abolishes palmitolyation of OspA.”
t0“Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis”
Claim · model-written summary
An N-terminal eukaryotic motif did not palmitoylate OspA in chloroplasts.
- Taxon
- tobaccoNicotiana tabacumt0
- Treatment
- N-terminal eukaryotic lipidation motife0
- Gene
- OspAe0
- Outcome
- palmitoylatione0
- Direction
- does not lead toe0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“decoration of OspA with an N-terminal eukaryotic lipidation motif does not lead to palmitoylation in chloroplasts.”
t0“Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis”
Claim · model-written summary
The bacterial OspA signal peptide targeted protein to thylakoids.
- Taxon
- tobaccoNicotiana tabacumt0
- Gene
- OspAe0
- Outcome
- targets the protein to thylakoidse0
- Qualifier
- bacterial signal peptidee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the bacterial signal peptide of OspA efficiently targets the protein to thylakoids, and causes a mutant phenotype.”
t0“Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis”
Claim · model-written summary
The OspA signal peptide caused a mutant plant phenotype.
- Taxon
- tobaccoNicotiana tabacumt0
- Gene
- OspAe0
- Outcome
- mutant phenotypee0
- Qualifier
- bacterial signal peptidee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“the bacterial signal peptide of OspA efficiently targets the protein to thylakoids, and causes a mutant phenotype.”
t0“Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis”
Claim · model-written summary
Plants accumulating OspA at 10% total soluble protein needed supplied sugars and died after greenhouse soil transfer.
- Taxon
- tobaccoNicotiana tabacumt0
- Gene
- OspAe0
- Outcome
- could not grow without exogenously supplied sugars and rapidly diede0
- Value
- 10% total soluble proteine0
- Setting
- greenhouse conditionse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Plants accumulating OspA at 10% total soluble protein could not grow without exogenously supplied sugars and rapidly died after transfer to soil under greenhouse conditions.”
t0“Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis”
Claim · model-written summary
OspA-expressing plants were strongly affected in photosystem II activity.
- Taxon
- tobaccoNicotiana tabacumt0
- Outcome
- photosystem IIe0
- Direction
- strongly affectede0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The plants were found to be strongly affected in photosystem II, as revealed by the analyses of temporal and spatial dynamics of photosynthetic activity by chlorophyll fluorescence imaging.”
t0“Expression of the recombinant bacterial outer surface protein A in tobacco chloroplasts leads to thylakoid localization and loss of photosynthesis”
The same questions in other papers
climate site · quality: protein · Nicotiana tabacum (tobacco)Positive and negative results
1 in the opposite direction
- no effect
loss of function · quality: protein · Nicotiana tabacum (tobacco)Positive and negative results
3 papers in the same direction as this paper · 3 in the opposite direction
- positive
- positive
- positive
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.