Crystallographic structure of a tetramer of jack bean concanavalin A (the monomers are colored cyan, green, red, and magenta respectively). Calcium (gold) and manganesecations (grey) are depicted as spheres.[1]
Concanavalin A (ConA) is a lectin (carbohydrate-binding protein) originally extracted from the jack-bean (Canavalia ensiformis). It is a member of the legume lectin family. It binds specifically to certain structures found in various sugars, glycoproteins, and glycolipids, mainly internal and nonreducing terminal α-D-mannosyl and α-D-glucosyl groups.[2][3] Its physiological function in plants, however, is still unknown. ConA is a plant mitogen, and is known for its ability to stimulate mouse T-cell subsets giving rise to four functionally distinct T cell populations, including precursors to regulatory T cells;[4] a subset of human suppressor T-cells is also sensitive to ConA.[4] ConA was the first lectin to be available on a commercial basis, and is widely used in biology and biochemistry to characterize glycoproteins and other sugar-containing entities on the surface of various cells.[5] It is also used to purify glycosylated macromolecules in lectin affinity chromatography,[6] as well as to study immune regulation by various immune cells.[4]
^PDB: 3CNA; Hardman KD, Ainsworth CF (December 1972). "Structure of concanavalin A at 2.4-A resolution". Biochemistry. 11 (26): 4910–4919. doi:10.1021/bi00776a006. PMID4638345.
