Topaquinone

Last updated
Topaquinone
Topaquinone structure.svg
Names
IUPAC name
(2S)-2-Amino-3-(4-hydroxy-3,6-dioxocyclohexa-1,4-dien-1-yl)propanoic acid
Other names
6-Hydroxydopaquinone
Identifiers
PubChem CID
Properties
C9H9NO5
Molar mass 211.173 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Topaquinone (TPQ) is a redox cofactor derived from the amino acid tyrosine. Its name derives from 2,4,5-trihydroxyphenylalanine-quinone. Its structure was first identified in 1990. [1] It is used by copper amine oxidases which contain a tyrosine residue near the active site. This residue catalyses its own transition, first to dopaquinone and then to topaquinone, in a Cu2+ dependent manner. [1]

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References

  1. 1 2 Dooley, D. M. (Feb 1999). "Structure and biogenesis of topaquinone and related cofactors". Journal of Biological Inorganic Chemistry. 4 (1): 1–11. doi:10.1007/s007750050283. ISSN   0949-8257. PMID   10499097. S2CID   10104769.