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Chemical Compound Review

dopaquinone     (2S)-2-amino-3-(3,4-dioxo-1- cyclohexa-1,5...

Synonyms: L-dopaquinone, o-Dopaquinone, SureCN5300667, CHEBI:16852, HMDB01229, ...
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Disease relevance of L-dopaquinone


High impact information on L-dopaquinone


Biological context of L-dopaquinone

  • In the enzyme case, hydration of dopaquinone is proposed to be mediated by the active site Cu(II) [6].
  • However, simultaneous measurements of ultraviolet-visible absorption spectra and oxygen consumption led us to conclude that the inhibition was due to oxidation of 6-tetrahydrobiopterin by dopaquinone [7].
  • We have synthesized cyclodopa and examined the kinetics of the formation of dopachrome following the pulse radiolytic generation of dopaquinone in its presence [8].
  • It is proposed that the synthesis of 5-S-CD is a mechanism regulating dopaquinone levels during pigment formation and/or a defence mechanism against oxidative stress [9].

Anatomical context of L-dopaquinone


Associations of L-dopaquinone with other chemical compounds

  • The consensus mechanism for biogenesis of the 2,4,5-trihydroxyphenylalanine quinone (TPQ) cofactor in copper amine oxidases involves a key water addition to the dopaquinone intermediate [6].
  • Reactions between in situ generated 4-ethyl-1,2-benzoquinone and primary amines give a mixture of products, indicating that the protein environment must play an essential role in LTQ biogenesis by directing the nucleophilic addition of the epsilon-amino group of a lysine residue to the C(4) position of a putative dopaquinone intermediate [14].
  • Tyrosinase inactivation also occurred when ascorbic acid was added to the reaction system; in which dopaquinone, an oxidation product of dopa which is immediately converted back to dopa by ascorbic acid thus preventing melanin formation [15].
  • A pulse radiolytic investigation has been conducted to establish whether a redox reaction takes place between dopaquinone and 5,6-dihydroxyindole (DHI) and its 2-carboxylic acid (DHICA) and to measure the rate constants of the interactions [16].
  • It is proposed that the oxidative engine of melanogenesis resides in an oxidation/reduction cycle involving Dopa and dopaquinone and that this can be modified by processes that result in the removal of dopaquinone or Dopa from the reaction system [17].

Gene context of L-dopaquinone


Analytical, diagnostic and therapeutic context of L-dopaquinone

  • We have examined quantitatively the role of dopaquinone in the non-enzymatic oxidation of 5-S-cysteinyldopa using pulse radiolysis and have demonstrated that the redox exchange reaction between dopaquinone and 5-S-cysteinyldopa occurs spontaneously with a rate constant of 8.8 x 10(5) M(-1) sec(-1) [23].


  1. Ectopic expression of tyrosine hydroxylase in the pigmented epithelium rescues the retinal abnormalities and visual function common in albinos in the absence of melanin. Lavado, A., Jeffery, G., Tovar, V., de la Villa, P., Montoliu, L. J. Neurochem. (2006) [Pubmed]
  2. Dopaquinone addition products in cultured human melanoma cells. Carstam, R., Hansson, C., Lindbladh, C., Rorsman, H., Rosengren, E. Acta Derm. Venereol. (1987) [Pubmed]
  3. Tyrosinase autoactivation and the chemistry of ortho-quinone amines. Land, E.J., Ramsden, C.A., Riley, P.A. Acc. Chem. Res. (2003) [Pubmed]
  4. Linking adhesive and structural proteins in the attachment plaque of Mytilus californianus. Zhao, H., Waite, J.H. J. Biol. Chem. (2006) [Pubmed]
  5. Tyrosinase isozyme heterogeneity in differentiating B16/C3 melanoma. Laskin, J.D., Piccinini, L.A. J. Biol. Chem. (1986) [Pubmed]
  6. A dopaquinone model that mimics the water addition step of cofactor biogenesis in copper amine oxidases. Ling, K.Q., Sayre, L.M. J. Am. Chem. Soc. (2005) [Pubmed]
  7. Indirect oxidation of 6-tetrahydrobiopterin by tyrosinase. Jung, J.H., Choi, S.W., Han, S. Biochem. Biophys. Res. Commun. (2004) [Pubmed]
  8. Rate constants for the first two chemical steps of eumelanogenesis. Land, E.J., Ito, S., Wakamatsu, K., Riley, P.A. Pigment Cell Res. (2003) [Pubmed]
  9. Cysteine-dependent 5-S-cysteinyldopa formation and its regulation by glutathione in normal epidermal melanocytes. Benathan, M., Labidi, F. Arch. Dermatol. Res. (1996) [Pubmed]
  10. Recent advances in the chemistry of melanogenesis in mammals. Prota, G. J. Invest. Dermatol. (1980) [Pubmed]
  11. An oxygen transporter hemocyanin can act on the late pathway of melanin synthesis. Adachi, K., Wakamatsu, K., Ito, S., Miyamoto, N., Kokubo, T., Nishioka, T., Hirata, T. Pigment Cell Res. (2005) [Pubmed]
  12. Generalized melanosis in metastatic malignant melanoma: the possible role of DOPAquinone metabolites. Tsukamoto, K., Furue, M., Sato, Y., Takayama, O., Akasu, R., Ohtake, N., Wakamatsu, K., Ito, S., Tamaki, K., Shimada, S. Dermatology (Basel) (1998) [Pubmed]
  13. Egg chorion tanning in Aedes aegypti mosquito. Li, J. Comp. Biochem. Physiol. A Physiol. (1994) [Pubmed]
  14. Synthesis and characterization of model compounds of the lysine tyrosyl quinone cofactor of lysyl oxidase. Mure, M., Wang, S.X., Klinman, J.P. J. Am. Chem. Soc. (2003) [Pubmed]
  15. Inactivation of tyrosinase by dopa. Tomita, Y., Hariu, A., Mizuno, C., Seiji, M. J. Invest. Dermatol. (1980) [Pubmed]
  16. Dopaquinone redox exchange with dihydroxyindole and dihydroxyindole carboxylic acid. Edge, R., d'Ischia, M., Land, E.J., Napolitano, A., Navaratnam, S., Panzella, L., Pezzella, A., Ramsden, C.A., Riley, P.A. Pigment Cell Res. (2006) [Pubmed]
  17. Mechanistic aspects of the control of tyrosinase activity. Riley, P.A. Pigment Cell Res. (1993) [Pubmed]
  18. Intracellular vesicular trafficking of tyrosinase gene family protein in eu- and pheomelanosome biogenesis. Jimbow, K., Hua, C., Gomez, P.F., Hirosaki, K., Shinoda, K., Salopek, T.G., Matsusaka, H., Jin, H.Y., Yamashita, T. Pigment Cell Res. (2000) [Pubmed]
  19. High-performance liquid chromatography (HPLC) analysis of eu- and pheomelanin in melanogenesis control. Ito, S. J. Invest. Dermatol. (1993) [Pubmed]
  20. Oxidation of tyrosine residues in proteins by tyrosinase. Formation of protein-bonded 3,4-dihydroxyphenylalanine and 5-S-cysteinyl-3,4-dihydroxyphenylalanine. Ito, S., Kato, T., Shinpo, K., Fujita, K. Biochem. J. (1984) [Pubmed]
  21. Agouti alleles influence thiol concentrations in hair follicles and extrafollicular tissues of mice (Ay/a, AwJ/AwJ, a/a). Granholm, D.E., Reese, R.N., Granholm, N.H. Pigment Cell Res. (1995) [Pubmed]
  22. Role of tyrosinase in the genoprotective effect of the edible mushroom, Agaricus bisporus. Shi, Y.L., Benzie, I.F., Buswell, J.A. Life Sci. (2002) [Pubmed]
  23. Spontaneous redox reactions of dopaquinone and the balance between the eumelanic and phaeomelanic pathways. Land, E.J., Riley, P.A. Pigment Cell Res. (2000) [Pubmed]
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