Shown here are the amino acid sequences of the wild-type and three mutant forms of a short protein.
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Wild-type: Met-Trp-Tyr-Arg-Gly-Ser-Pro-Thr
Mutant 1: Met-Trp
Mutant 2: Met-Trp-His-Arg-Gly-Ser-Pro-Thr
Mutant 3: Met-Cys-Ile-Val-Val-Val-Gln-His                                  _

Use this information to answer the following questions:

Using the genetic coding dictionary, predict the type of mutation that led to each altered protein.

Verified step by step guidance

1. Identify the differences between the wild-type and each mutant sequence.
2. For Mutant 1, note that the sequence is truncated after 'Met-Trp'. This suggests a possible nonsense mutation, where a stop codon was introduced early.
3. For Mutant 2, observe that 'His' is inserted after 'Trp'. This could be due to a missense mutation where a single nucleotide change resulted in a different amino acid.
4. For Mutant 3, the entire sequence is different starting from the second amino acid. This suggests a frameshift mutation, likely due to an insertion or deletion, altering the reading frame.
5. Use the genetic code to verify the possible codon changes that could lead to these mutations.

Key Concepts

Amino Acids and Protein Structure

Amino acids are the building blocks of proteins, and their specific sequence determines a protein's structure and function. Each amino acid is encoded by a set of three nucleotides in DNA, known as a codon. Changes in the amino acid sequence can lead to different protein properties, which is crucial for understanding mutations.

Types of Mutations

Mutations are changes in the DNA sequence that can affect the resulting protein. Common types include point mutations (single nucleotide changes), insertions (adding nucleotides), and deletions (removing nucleotides). Each type can lead to different outcomes, such as silent mutations, missense mutations, or nonsense mutations, which can alter protein function.

Genetic Code and Codon Usage

The genetic code is a set of rules that defines how nucleotide sequences are translated into amino acids. Each codon corresponds to a specific amino acid or a stop signal. Understanding the genetic code is essential for predicting the effects of mutations on protein sequences, as it allows for the identification of which amino acids are affected by changes in the DNA.