The partial amino acid sequence of a wild-type protein is … Arg-Met-Tyr-Thr-Leu-Cys-Ser … The same portion of the protein from a mutant has the sequence … Arg-Met-Leu-Tyr-Ala-Leu-Phe … Give the sequence of the wild-type DNA template strand. Use A/G if the nucleotide could be either purine, T/C if it could be either pyrimidine, N if any nucleotide could occur at a site, or the alternative nucleotides if a purine and a pyrimidine are possible.

Key Concepts

Genetic Code

The genetic code is a set of rules that defines how the sequence of nucleotides in DNA corresponds to the sequence of amino acids in proteins. Each amino acid is encoded by a triplet of nucleotides, known as a codon. Understanding the genetic code is essential for translating the amino acid sequences back into the corresponding DNA sequences.

DNA Template Strand

The DNA template strand is the strand of DNA that serves as a template for RNA synthesis during transcription and for DNA replication. It is complementary to the coding strand and dictates the sequence of nucleotides in the newly synthesized strand. Knowing how to derive the template strand from an amino acid sequence is crucial for solving the given problem.

Mutations and Their Effects

Mutations are changes in the nucleotide sequence of DNA that can lead to alterations in protein structure and function. Understanding how mutations can affect amino acid sequences helps in identifying the differences between wild-type and mutant proteins. This knowledge is important for determining how to reconstruct the wild-type DNA sequence from the provided mutant sequence.