The term alpha chain is normally used to indicate one of the subunits of a multi-subunit protein. The term "chain" is a general term given to any peptide sequence. It can often refer more specifically to mean: a part of the T-cell receptor, the fibrinogen alpha chain, the integrin alpha chain, Hemoglobin, alpha 1
It should be distinguished from the term alpha helix, which refers to one of the common secondary structures found in proteins, along with beta sheet.
See also Fibrinogen Peptide
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