Recombinant Arabis hirsuta Photosystem II CP47 chlorophyll apoprotein (psbB)
Description
Functional Role in Photosynthesis
2.1 PSII Core Complex Assembly
PsbB anchors chlorophyll and stabilizes the PSII reaction center, enabling:
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Water Oxidation: Extraction of electrons from H₂O, producing O₂ and a proton gradient .
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Electron Transfer: Coordination of light-induced redox reactions via chlorophyll a and pheophytin .
2.2 Repair and Stability
Under high light, psbB participates in PSII repair cycles:
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Damaged D1 Protein Replacement: PsbB remains intact while photodamaged D1 is degraded .
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Reassembly: Reintegration of new D1 and auxiliary subunits (e.g., CP43, oxygen-evolving complex) .
Recombinant Production and Applications
3.1 Expression Systems
PsbB is typically recombinant-expressed in E. coli with an N-terminal His-tag for purification .
| Parameter | Details |
|---|---|
| Tag Type | His-tag (e.g., Spinacia oleracea psbB ) |
| Storage | -20°C or -80°C in Tris-based buffer with 50% glycerol . |
| Purity | >90% by SDS-PAGE . |
Research Applications
Comparative Genomic Insights
4.1 Chloroplast Genome Context
In A. hirsuta, psbB resides in the large single-copy (LSC) region of the chloroplast genome, mirroring other Brassicaceae species . Notably:
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Gene Conservation: Absence of rps16 and infA in Arabis plastomes, reflecting lineage-specific pseudogenization .
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Evolutionary Links: Closer to Draba than Arabidopsis, per phylogenetic analyses .
4.2 Substitution Rates
In Arabis stellari, the Ka/Ks ratio for ndhA (a stress-related gene) vs. A. hirsuta is 1.35, suggesting relaxed purifying selection .
Key Research Findings
5.1 Structural Modeling
Electron crystallography of spinach CP47 revealed:
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5 Chlorophylls directly ligated to histidines (Mg²⁺ within 4 Å).
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7 Chlorophylls in proximity (4–8 Å), necessitating indirect coordination .
5.2 Functional Impact
PsbB mutations impair PSII activity, as seen in Oenothera hybrids with reduced psbB mRNA and CP47 levels, leading to abnormal chloroplast development .
Product Specs
Note: We will prioritize shipping the format currently in stock. However, if you have specific format requirements, please specify them in your order remarks. We will prepare the product according to your request.
Note: All our proteins are shipped with standard blue ice packs. If you require dry ice shipping, please inform us in advance. Additional fees may apply.
Generally, the shelf life of liquid form is 6 months at -20°C/-80°C. The shelf life of lyophilized form is 12 months at -20°C/-80°C.
