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9.2: Exercise 1 - The 1-letter code for amino acids

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  • You may find NCBI’s Amino Acid Explorer helpful for this exercise. You can access Amino Acid Explorer through Google or directly at:

    1. Under the amino sequence below, write the same sequence using the 1-letter code. Met-Glu-Asn-Asp-Glu-Leu-Pro-Ile-Cys-Lys-Glu-Asp-Pro-Glu-Cys-Lys-Glu-Asp

    2. What is the net charge of this peptide? (Assign -1 for each acidic amino acid and +1 for each basic amino acid. Add up the total charges.)

    3. Using the Venn diagram above, propose a conservative substitution for:
    Trp - His - ​​​​​​​Arg - ​​​​​​​​​​​​​​Leu -

    4. Write the name of a music group that you enjoy. Then transpose the name into an amino acid sequence written with the 3-letter code. Pass the amino acid sequence to a friend and have him/her decode it. (Note: the 1-letter code uses all of the alphabet, except B, J, O, U, X and Z).