6. Protein Synthesis 5

TL;DR

The method of re-engineering translation allows for the incorporation of unnatural amino acids into proteins, using a unique codon and specific tRNA and aminoacyl tRNA synthetase.

Transcript

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Key Insights

• ❓ Re-engineering translation involves assigning a unique codon for the incorporation of unnatural amino acids into proteins.
• ❓ The choice of codon is crucial, as it should not be frequently used or involved in the termination of essential genes.
• ❓ Specific tRNA and aminoacyl tRNA synthetase are necessary to ensure the incorporation of the unnatural amino acid into the protein.

Questions & Answers

Q: Why is it important to assign a unique codon for the incorporation of an unnatural amino acid?

Assigning a unique codon ensures specificity and allows for the precise placement of the unnatural amino acid in a protein.

Q: What is the role of a specific tRNA in this process?

The specific tRNA recognizes the unique codon and is responsible for carrying the unnatural amino acid to the ribosome for incorporation into the growing protein chain.

Q: How does the aminoacyl tRNA synthetase contribute to the re-engineering of translation?

The aminoacyl tRNA synthetase is responsible for attaching the unnatural amino acid to the tRNA, ensuring its correct incorporation into the protein.

Q: What are the considerations when choosing an appropriate codon for re-assignment?

The frequency of use of the codon and whether it terminates essential genes are important factors to consider when selecting a codon for re-assignment.

Summary & Key Takeaways

• The re-engineering of translation involves assigning a unique codon for the incorporation of an unnatural amino acid into proteins.

• The key components required for this process are a unique codon, a specific tRNA that recognizes the codon, and an aminoacyl tRNA synthetase to attach the unnatural amino acid to the tRNA.

• The amber stop codon (TAG) is often re-assigned as the codon for the unnatural amino acid due to its low frequency of use and lack of termination of essential genes.