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Amino Acid Structure

An alpha-amino acid has an amino group, a carboxyl group, a hydrogen and a variable side chain on the same carbon, existing as a zwitterion near neutral pH. The twenty proteinogenic side chains differ in charge, polarity, bulk and reactivity, and each reactive side chain needs its own protecting group during synthesis.

Questions this Concept answers

Explain why a free amino acid exists predominantly as a zwitterion in solution near neutral pH.

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Amino Acids in Biochemistry: Structure and Function as Protein Monomers

Amino acids function as monomeric units defined by a central alpha carbon bearing variable side chains (R-groups) that dictate specific chemical properties such as hydrophobicity, acidity, basicity, …