Recombinant Thermus thermophilus 30S ribosomal protein S3 (rpsC)
Description
Functional Roles
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mRNA decoding: Stabilizes the mRNA-ribosome complex during translation initiation .
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Ribosome assembly: Acts as a secondary binding protein, dependent on primary assembly proteins like S7 for proper integration into the 30S subunit .
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Thermostability: Contributes to the structural integrity of the 30S subunit at high temperatures (up to 65°C) .
Recombinant Production
Expression systems:
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Typically expressed in E. coli (e.g., BL21 strain) using plasmids with strong promoters (e.g., T7) .
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Requires thermophilic codon optimization and co-expression with chaperones to prevent misfolding in mesophilic hosts .
Purification challenges:
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Inclusion body formation mitigated by low-temperature induction (25–30°C) and polyamine supplementation .
Research Findings
Assembly dependencies:
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S3 binding to the 30S subunit requires prior association of S7 and S9, as shown by in vitro reconstitution assays .
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Structural studies indicate conformational changes in 16S rRNA (e.g., helix 34) upon S3 binding, critical for decoding fidelity .
Functional compatibility:
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Hybrid ribosomes containing T. thermophilus S3 and E. coli components retain partial activity, highlighting evolutionary conservation .
Thermal adaptation:
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S3’s surface residues (e.g., charged amino acids) enhance thermostability by forming salt bridges and reducing conformational flexibility .
Applications and Implications
Product Specs
Target Background
KEGG: ttj:TTHA1686
STRING: 300852.TTHA1686
