alpha amino acid

chemical compound

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June 18, 2026

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An alpha-amino acid is an organic molecule characterized by an amino group (\u2015NH₂), a carboxyl group (\u2015COOH), and a unique organic side chain (R group), all attached to a central carbon atom (the \u03b1-carbon). These molecules are the fundamental building blocks of proteins, which are essential for catalyzing biochemical reactions, providing structural support, and binding cells together. There are over 100 known amino acids, but only 20 are commonly found in most proteins, linked by peptide bonds. The specific sequence and types of amino acids determine a protein's unique properties and functions.123

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protein
The amino acid composition of proteins
…consist of long chains of α-amino (alpha amino) acids. The α-amino acids are so called because the α-carbon atom in the molecule carries an amino group (―NH₂); the α-carbon atom also carries a carboxyl group (―COOH).
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…consist of long chains of α-amino (alpha amino) acids. The α-amino acids are so called because the α-carbon atom in the molecule carries an amino group (―NH₂); the α-carbon atom also carries a carboxyl group (―COOH).
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