Consider the amino acids glycine, proline, and lysine.
b. Using three-letter abbreviations for the amino acids, give the sequence for each of the possible tripeptides.

Verified step by step guidance

1. Identify the three amino acids given in the problem: glycine (Gly), proline (Pro), and lysine (Lys). These are the building blocks for the tripeptides.
2. Understand that a tripeptide is a sequence of three amino acids linked together by peptide bonds. The order of the amino acids in the sequence matters, so each unique arrangement represents a different tripeptide.
3. Determine the total number of possible sequences. Since there are three amino acids and each position in the tripeptide can be occupied by any of the three amino acids, the number of permutations is calculated as 3! (3 factorial), which equals 6.
4. List all possible sequences using the three-letter abbreviations for the amino acids. The sequences are: Gly-Pro-Lys, Gly-Lys-Pro, Pro-Gly-Lys, Pro-Lys-Gly, Lys-Gly-Pro, and Lys-Pro-Gly.
5. Verify that all six sequences are unique and that no sequence is repeated. This ensures that all possible tripeptides have been accounted for.

Key Concepts

Amino Acids

Amino acids are organic compounds that serve as the building blocks of proteins. Each amino acid has a specific structure, consisting of a central carbon atom, an amino group, a carboxyl group, a hydrogen atom, and a variable side chain (R group) that determines its properties. Glycine (Gly), proline (Pro), and lysine (Lys) are three distinct amino acids, each with unique characteristics that influence protein structure and function.

Tripeptides

Tripeptides are molecules formed by the linkage of three amino acids through peptide bonds. The sequence in which the amino acids are arranged is crucial, as it determines the tripeptide's properties and biological function. The order of amino acids can vary, leading to different tripeptides even if the same amino acids are used, highlighting the importance of sequence in protein chemistry.

Three-Letter Abbreviations

Three-letter abbreviations are standardized codes used to represent amino acids in a concise manner. For example, glycine is abbreviated as 'Gly', proline as 'Pro', and lysine as 'Lys'. These abbreviations facilitate easier communication and notation in biochemistry, especially when discussing sequences of amino acids in proteins or peptides.