Third-base wobble allows some tRNAs to recognize more than one mRNA codon. Based on this chapter's discussion of wobble, what is the minimal number of tRNA molecules necessary to recognize the following amino acids?

lysine

Verified step by step guidance

1. Understand the concept of wobble: The wobble hypothesis explains how a single tRNA can recognize multiple codons for the same amino acid. This is due to the flexibility in base pairing at the third position of the codon.
2. Identify the codons for lysine: Lysine is encoded by two codons, AAA and AAG.
3. Determine the anticodons: The anticodons that pair with AAA and AAG are UUU and UUC, respectively.
4. Apply the wobble rules: According to the wobble hypothesis, the third position of the anticodon can pair with more than one base. In this case, U at the first position of the anticodon can pair with both A and G at the third position of the codon.
5. Conclude the minimal number of tRNAs: Since one tRNA with the anticodon UUU can recognize both AAA and AAG due to wobble, only one tRNA is necessary to recognize lysine.

Key Concepts

Wobble Hypothesis

The wobble hypothesis explains how the third base of a codon can pair loosely with the corresponding tRNA anticodon, allowing a single tRNA to recognize multiple codons. This flexibility reduces the number of tRNA molecules required for protein synthesis, as one tRNA can accommodate variations in the third position of codons that code for the same amino acid.

tRNA and Codons

Transfer RNA (tRNA) molecules are responsible for bringing amino acids to the ribosome during protein synthesis. Each tRNA has an anticodon that pairs with a specific mRNA codon, which is a sequence of three nucleotides that codes for a particular amino acid. Understanding the relationship between tRNA and codons is essential for determining how many tRNAs are needed for a given set of amino acids.

Amino Acids and Their Codons

Amino acids are the building blocks of proteins, and each amino acid is encoded by one or more codons in the genetic code. For lysine, there are two codons (AAA and AAG) that specify this amino acid. Recognizing the codons associated with lysine is crucial for determining the minimal number of tRNA molecules required to translate the corresponding mRNA.