There are 20 amino acids that make up proteins and all have the same basic structure, differing only in the R-group or side chain they have. Amino acids are in an equilibrium between two acids with ...

Each of the 20 amino acids has a specific side chain, known as an R group, that is also attached to the α carbon. The R groups have a variety of shapes, sizes, charges, and reactivities.

The carbon atom forms a bond with a hydrogen atom, an amino group, a carboxylic acid group, and an R group. An R group is a unique side chain that differentiates between each amino acid.

Amino acids are characterized by their central carbon atom, known as the α-carbon, which is bonded to an amino group (-NH2), a carboxyl group (-COOH), a hydrogen atom, and a variable side chain ...

NASA’s OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) mission has detected amino acids in the largest asteroid sample ever collected in space, ...

The defining feature of an amino acid is its side chain (at top, blue circle; below, all colored circles). When connected together by a series of peptide bonds, amino acids form a polypeptide ...