What is the monomer of proteins?

The monomers of proteins are amino acids. There are 20 different standard amino acids that are commonly incorporated into proteins during translation. Each amino acid has a central carbon atom (the alpha carbon) bonded to:

• An amino group (-NH2): This is a basic group.
• A carboxyl group (-COOH): This is an acidic group.
• A hydrogen atom (-H).
• A side chain (R-group): This is what distinguishes one amino acid from another. The R-group can be anything from a simple hydrogen atom (as in glycine) to a complex ring structure (as in tryptophan). The properties of the R-group (e.g., hydrophobic, hydrophilic, charged, polar) greatly influence the overall structure and function of the protein.

These amino acids link together through peptide bonds, a type of covalent bond formed between the carboxyl group of one amino acid and the amino group of another, releasing a water molecule in the process. A chain of amino acids linked by peptide bonds is called a polypeptide, and one or more polypeptides folded into a specific 3D structure constitutes a protein.