Editing Locant (section)

===Proteins and amino acids===
In [[protein]]s and [[amino acid]]s, the α-carbon is the backbone carbon before the carbonyl carbon atom in the molecule. Therefore, reading along the backbone of a typical protein would give a sequence of –[N—Cα—carbonyl C]<sub>n</sub>– etc. (when reading in the N to C direction). The α-carbon is where the different substituents attach to each different amino acid. That is, the groups hanging off the chain at the α-carbon are what give amino acids their diversity. These groups give the α-carbon its [[stereogenic]] properties for every amino acid except for [[glycine]]. Therefore, the α-carbon is a [[stereocenter]] for every amino acid except glycine. Glycine also does not have a β-carbon, while every other amino acid does.

The α-carbon of an amino acid is significant in [[protein folding]]. When describing a protein, which is a chain of amino acids, one often approximates the location of each amino acid as the location of its α-carbon. In general, α-carbons of adjacent amino acids in a protein are about 3.8 [[ångström]]s (380 [[picometer]]s) apart.