Recombinant Sinorhizobium medicae ATP synthase subunit beta (atpD), partial
Description
Functional Role of ATP Synthase in Sinorhizobium medicae
ATP synthase is essential for energy metabolism, coupling proton gradient-driven rotation to ATP synthesis. In S. medicae, ATP synthase activity supports nitrogen fixation in root nodules by fueling the energy-intensive process of converting atmospheric N₂ to ammonia .
Key Features of atpD:
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Encodes the β-subunit of the F1 sector, responsible for ATP synthesis.
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Plays a role in maintaining cellular ATP levels during symbiosis .
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Homologs in S. meliloti (e.g., SM0020_11415) are linked to stress adaptation, suggesting potential cross-species functional conservation .
Recombinant atpD: Production and Applications
Recombinant atpD refers to a truncated version of the protein expressed in heterologous systems (e.g., E. coli) for biochemical or structural studies.
Typical Workflow for Recombinant atpD Production:
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Gene Cloning: Amplification of the partial atpD sequence from S. medicae genomic DNA.
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Vector Design: Insertion into expression plasmids (e.g., pET or pGEX systems).
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Protein Expression: Induction with IPTG in E. coli BL21 strains.
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Purification: Affinity chromatography (e.g., His-tag purification).
Challenges:
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Truncated forms may lack functional domains, necessitating activity assays.
Comparative Analysis of atpD Homologs
While S. medicae atpD-specific data is sparse, studies on S. meliloti and other rhizobia highlight its importance:
Research Gaps and Future Directions
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Functional Characterization: Direct assays of recombinant S. medicae atpD’s enzymatic activity are needed.
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Structural Studies: Cryo-EM or X-ray crystallography could resolve truncated protein dynamics.
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Symbiotic Role: Knockout mutants could clarify atpD’s contribution to nitrogen fixation efficiency .
Implications for Agricultural Biotechnology
Enhancing ATP synthase efficiency in rhizobia could improve legume productivity under stress. For example, S. medicae strains with optimized atpD might better sustain nitrogen fixation in acidic soils, where they exhibit a competitive edge over S. meliloti .
Product Specs
Target Background
KEGG: smd:Smed_2922
STRING: 366394.Smed_2922
