catechol oxidase


Summary: An enzyme of the oxidoreductase class that catalyzes the reaction between catechol and oxygen to yield benzoquinone and water. It is a complex of copper-containing proteins that acts also on a variety of substituted catechols. EC

Top Publications

  1. Aka J, Courtois F, Louarme L, Nicolas J, Billaud C. Modelling the interactions between free phenols, L-ascorbic acid, apple polyphenoloxidase and oxygen during a thermal treatment. Food Chem. 2013;138:1289-97 pubmed publisher
    ..Results also confirmed that AA in excess induced a fast regeneration of CG and EPI from the corresponding o-quinones formed enzymatically via redox chemical reactions. ..
  2. Shetty S, Chandrashekar A, Venkatesh Y. Eggplant polyphenol oxidase multigene family: cloning, phylogeny, expression analyses and immunolocalization in response to wounding. Phytochemistry. 2011;72:2275-87 pubmed publisher
    ..Our results show that eggplant PPO genes are structurally different, and are differentially expressed in various tissues of eggplant indicating their functional diversity...
  3. Asano T, Takebuchi K. Identification of the gene encoding pro-phenoloxidase A(3) in the fruitfly, Drosophila melanogaster. Insect Mol Biol. 2009;18:223-32 pubmed publisher
    ..These results indicate that the expression of CG2952 is very low and that CG8193 is the gene that encodes proPO A3. Processing of A(1)and A(3) isoforms in adult homogenate and activity of recombinant proPOs were also investigated. ..
  4. Nam H, Jang I, Asano T, Lee W. Involvement of pro-phenoloxidase 3 in lamellocyte-mediated spontaneous melanization in Drosophila. Mol Cells. 2008;26:606-10 pubmed
    ..Taken together, these findings indicate that the biochemical properties, activation mode and in vivo role of Pro-PO3 are likely distinct from those of the other two Pro-PO enzymes involved in Drosophila physiology. ..
  5. Diao Y, Lu A, Yang B, Hu W, Peng Q, Ling Q, et al. Existence of prophenoloxidase in wing discs: a source of plasma prophenoloxidase in the silkworm, Bombyx mori. PLoS ONE. 2012;7:e41416 pubmed publisher
    ..Therefore, this might be another source of plasma PPO in the silkworm: some infiltrated hemocytes sourced from the hematopoietic organ release PPO via wing discs. ..
  6. Wang Z, Lu A, Li X, Shao Q, Beerntsen B, Liu C, et al. A systematic study on hemocyte identification and plasma prophenoloxidase from Culex pipiens quinquefasciatus at different developmental stages. Exp Parasitol. 2011;127:135-41 pubmed publisher
    ..These results are forming a basis for further studies on the function of C. quinquefasciatus hemocytes and prophenoloxidase as well as their involvement in fighting against mosquito-borne pathogens...
  7. Wang Y, Hao H, Qiu Z, Xu W, Zhang J, Zhou T, et al. Involvement of prophenoloxidases in the suppression of Plasmodium yoelii development by Anopheles dirus. Exp Parasitol. 2009;123:6-10 pubmed publisher
    ..This depletion increased P. yoelii infection prevalence and oocyst intensity, and abolished the melanization of oocysts as well. Therefore, An. dirus PPOs may play a role in the refractoriness to P. yoelii. ..
  8. Yu Y, Tang T, Qian Q, Wang Y, Yan M, Zeng D, et al. Independent losses of function in a polyphenol oxidase in rice: differentiation in grain discoloration between subspecies and the role of positive selection under domestication. Plant Cell. 2008;20:2946-59 pubmed publisher
    ..This case may hence represent an example of artificial selection driving the differentiation among domesticated varieties. ..
  9. Plazas M, López Gresa M, Vilanova S, Torres C, Hurtado M, Gramazio P, et al. Diversity and relationships in key traits for functional and apparent quality in a collection of eggplant: fruit phenolics content, antioxidant activity, polyphenol oxidase activity, and browning. J Agric Food Chem. 2013;61:8871-9 pubmed publisher
    ..Results suggest that it is possible to develop new eggplant varieties with improved functional and apparent quality. ..

More Information


  1. Gasparetti C, Faccio G, Arvas M, Buchert J, Saloheimo M, Kruus K. Discovery of a new tyrosinase-like enzyme family lacking a C-terminally processed domain: production and characterization of an Aspergillus oryzae catechol oxidase. Appl Microbiol Biotechnol. 2010;86:213-26 pubmed publisher
    ..Because no activity was detected on L-tyrosine and on L-dopa, AoCO4 was classified as a catechol oxidase. AoCO4 showed the highest activity within an acidic and neutral pH range, having an optimum at pH 5.6...
  2. An C, Ishibashi J, Ragan E, Jiang H, Kanost M. Functions of Manduca sexta hemolymph proteinases HP6 and HP8 in two innate immune pathways. J Biol Chem. 2009;284:19716-26 pubmed publisher
  3. Scherfer C, Tang H, Kambris Z, Lhocine N, Hashimoto C, Lemaitre B. Drosophila Serpin-28D regulates hemolymph phenoloxidase activity and adult pigmentation. Dev Biol. 2008;323:189-96 pubmed publisher
    ..This study further highlights the complexity of the proPO cascade that can be differentially regulated in different tissues during development...
  4. Taketa S, Matsuki K, Amano S, Saisho D, Himi E, Shitsukawa N, et al. Duplicate polyphenol oxidase genes on barley chromosome 2H and their functional differentiation in the phenol reaction of spikes and grains. J Exp Bot. 2010;61:3983-93 pubmed publisher
    ..An insertion of a hAT-family transposon in the promoter region of PPO2 may be responsible for different expression patterns of the duplicate PPO genes in barley. ..
  5. Newman S, Tantasawat P, Steffens J. Tomato polyphenol oxidase B is spatially and temporally regulated during development and in response to ethylene. Molecules. 2011;16:493-517 pubmed publisher
    ..It was shown that PPO B expression was tissue specific, developmentally regulated, ethylene induced, and localized predominantly to mitotic or apoptotic tissues. ..
  6. Wahler D, Gronover C, Richter C, Foucu F, Twyman R, Moerschbacher B, et al. Polyphenoloxidase silencing affects latex coagulation in Taraxacum species. Plant Physiol. 2009;151:334-46 pubmed publisher
    ..In contrast, very little PPO activity is found in the latex of the rubber tree Hevea brasiliensis, suggesting functional divergence of latex proteins during plant evolution...
  7. Richter C, Dirks M, Gronover C, Prüfer D, Moerschbacher B. Silencing and heterologous expression of ppo-2 indicate a specific function of a single polyphenol oxidase isoform in resistance of dandelion (Taraxacum officinale) against Pseudomonas syringae pv. tomato. Mol Plant Microbe Interact. 2012;25:200-10 pubmed publisher
    ..tomato. These results clearly indicate a strong contribution of a specific, single PPO isoform to disease resistance. Therefore, we propose that specific PPO isoenzymes be included in a new family of pathogenesis-related (PR) proteins...
  8. An C, Kanost M. Manduca sexta serpin-5 regulates prophenoloxidase activation and the Toll signaling pathway by inhibiting hemolymph proteinase HP6. Insect Biochem Mol Biol. 2010;40:683-9 pubmed publisher
    ..These results indicate that serpin-5 may regulate the activity of HP6 to modulate proPO activation and antimicrobial peptide production during immune responses of M. sexta. ..
  9. Li Y, Wang Y, Jiang H, Deng J. Crystal structure of Manduca sexta prophenoloxidase provides insights into the mechanism of type 3 copper enzymes. Proc Natl Acad Sci U S A. 2009;106:17002-6 pubmed publisher
    ..A drastic change in electrostatic surface induced on cleavage at Arg-51 allows us to propose a model for localized PPO activation in insects. ..
  10. Olivares C, Solano F. New insights into the active site structure and catalytic mechanism of tyrosinase and its related proteins. Pigment Cell Melanoma Res. 2009;22:750-60 pubmed publisher
    ..The availability of crystallographic data of one plant catechol oxidase and one bacterial tyrosinase has improved the model of the three-dimensional structure of the active site of ..
  11. Phonpala Y, Benjakul S, Visessanguan W, Eun J. Sulfur-containing compounds heated under alkaline condition: antibrowning, antioxidative activities, and their effect on quality of shrimp during iced storage. J Food Sci. 2009;74:S240-7 pubmed publisher
    ..05). Therefore, heated alkaline cysteine can be used as a novel additive to retard melanosis and extend the quality of postmortem shrimp. ..
  12. Labbé P, Little T. ProPhenolOxidase in Daphnia magna: cDNA sequencing and expression in relation to resistance to pathogens. Dev Comp Immunol. 2009;33:674-80 pubmed publisher
    ..This is the first evidence of a Daphnia immune response, and our observations raise the possibility that the PhenolOxidase (PO) cascade is involved in the defence against pathogenic gram-positive bacteria. ..
  13. Tran L, Taylor J, Constabel C. The polyphenol oxidase gene family in land plants: Lineage-specific duplication and expansion. BMC Genomics. 2012;13:395 pubmed publisher
    ..The dynamic nature of this gene family differentiates PPO from other oxidative enzymes, and is consistent with a protein important for a diversity of functions relating to environmental adaptation. ..
  14. Chen Y, Liu F, Yang B, Lu A, Wang S, Wang J, et al. Specific amino acids affecting Drosophila melanogaster prophenoloxidase activity in vitro. Dev Comp Immunol. 2012;38:88-97 pubmed publisher
    ..Thus, we found that some amino acids are important for rPPO3 Cu(2+)-aided auto-activation as well as PPO staining activity in vitro. ..
  15. Ling W, Lu X, Gao Y, Liu J, Sun Y. Polyphenol oxidase activity in subcellular fractions of tall fescue contaminated by polycyclic aromatic hydrocarbons. J Environ Qual. 2012;41:807-13 pubmed publisher
    ..Our results provide new information on enzyme responses in plant intracellular fractions to xenobiotic POPs and fundamental information on within-plant POP metabolic mechanisms. ..
  16. Zou Z, Shin S, Alvarez K, Bian G, Kokoza V, Raikhel A. Mosquito RUNX4 in the immune regulation of PPO gene expression and its effect on avian malaria parasite infection. Proc Natl Acad Sci U S A. 2008;105:18454-9 pubmed publisher
    ..These findings suggest that RUNX4 regulates PPO gene expression under the control of the Toll pathway and plays a critical role in restricting parasite development...
  17. Tran L, Constabel C. The polyphenol oxidase gene family in poplar: phylogeny, differential expression and identification of a novel, vacuolar isoform. Planta. 2011;234:799-813 pubmed publisher
    ..Transient expression of green fluorescent protein fusions demonstrated its localization to the vacuolar lumen. Together, our findings show that the poplar PPO family is diverse and is likely linked to diverse physiological functions...
  18. Sumathipala N, Jiang H. Involvement of Manduca sexta peptidoglycan recognition protein-1 in the recognition of bacteria and activation of prophenoloxidase system. Insect Biochem Mol Biol. 2010;40:487-95 pubmed publisher
    ..The unexplained difference between the purified PGs and intact bacteria clearly reflects our general lack of understanding of PGRP1-mediated recognition and how it leads to proPO activation. ..
  19. Liu F, Chen Y, Yang B, Wang J, Peng Q, Shao Q, et al. Drosophila melanogaster prophenoloxidases respond inconsistently to Cu2+ and have different activity in vitro. Dev Comp Immunol. 2012;36:619-28 pubmed publisher
    ..The successful method for rPPO expression in S2 cells described in this paper will provide us with an opportunity to study the properties of a specific PPO gene in a small insect like mosquitoes in the future. ..
  20. Rompel A, Büldt Karentzopoulos K, Molitor C, Krebs B. Purification and spectroscopic studies on catechol oxidase from lemon balm (Melissa officinalis). Phytochemistry. 2012;81:19-23 pubmed publisher
    A catechol oxidase from lemon balm (Melissa officinalis) moCO which only catalyzes the oxidation of catechols to quinones without hydroxylating tyrosine was purified. The molecular mass of the M...
  21. Malviya N, Srivastava M, Diwakar S, Mishra S. Insights to sequence information of polyphenol oxidase enzyme from different source organisms. Appl Biochem Biotechnol. 2011;165:397-405 pubmed publisher
    ..Motif GGGMMGDVPTANDPIFWLHHCNVDRLWAVWQ was found in all the species of bacterial and fungus sources. In addition, seven new motifs which were unique for their group were also identified. ..
  22. Virador V, Reyes Grajeda J, Blanco Labra A, Mendiola Olaya E, Smith G, Moreno A, et al. Cloning, sequencing, purification, and crystal structure of Grenache (Vitis vinifera) polyphenol oxidase. J Agric Food Chem. 2010;58:1189-201 pubmed publisher
    ..The mass of the crystallized protein appears to be only 38.4 kDa, and the processing that occurs in the grape berry that leads to this smaller size is discussed...
  23. Winters A, Heywood S, Farrar K, Donnison I, Thomas A, Webb K. Identification of an extensive gene cluster among a family of PPOs in Trifolium pratense L. (red clover) using a large insert BAC library. BMC Plant Biol. 2009;9:94 pubmed publisher
    ..Molecular markers for a range of important agricultural traits are being developed for red clover and improved knowledge of PPO genes and their structure will facilitate molecular breeding...
  24. Li X, Ma M, Liu F, Chen Y, Lu A, Ling Q, et al. Properties of Drosophila melanogaster prophenoloxidases expressed in Escherichia coli. Dev Comp Immunol. 2012;36:648-56 pubmed publisher
  25. Shao Q, Yang B, Xu Q, Li X, Lu Z, Wang C, et al. Hindgut innate immunity and regulation of fecal microbiota through melanization in insects. J Biol Chem. 2012;287:14270-9 pubmed publisher
    ..Our analysis of the silkworm hindgut prophenoloxidase discloses the natural secret of why the phytophagous insect feces is black and provides insight into hindgut innate immunity, which is still rather unclear in mammals. ..
  26. Wang Y, Jiang H. Reconstitution of a branch of the Manduca sexta prophenoloxidase activation cascade in vitro: snake-like hemolymph proteinase 21 (HP21) cleaved by HP14 activates prophenoloxidase-activating proteinase-2 precursor. Insect Biochem Mol Biol. 2007;37:1015-25 pubmed
    ..In summary, we have discovered and reconstituted a branch of the proPO activation cascade in vitro: beta-1,3-glucan recognition--proHP14 autoactivation--proHP21 cleavage--PAP-2 generation--proPO activation--melanin formation...
  27. Shelby K, Adeyeye O, Okot Kotber B, Webb B. Parasitism-linked block of host plasma melanization. J Invertebr Pathol. 2000;75:218-25 pubmed
    ..Thus in CsIV-infected larvae, enzymatic deficiencies in the melanization pathway lead to reduced concentrations of specific enzyme substrates, causing failure of melanization in parasitized insects. ..
  28. Sullivan M, Hatfield R, Thoma S, Samac D. Cloning and characterization of red clover polyphenol oxidase cDNAs and expression of active protein in Escherichia coli and transgenic alfalfa. Plant Physiol. 2004;136:3234-44 pubmed
    ..Transgenic alfalfa expressing red clover PPO should prove an excellent model system to further characterize the red clover PPO enzymes and PPO-mediated inhibition of postharvest proteolysis in forage plants. ..
  29. Irving P, Ubeda J, Doucet D, Troxler L, Lagueux M, Zachary D, et al. New insights into Drosophila larval haemocyte functions through genome-wide analysis. Cell Microbiol. 2005;7:335-50 pubmed
    ..This shows that Drosophila haemocytes produce a signal molecule ready to be activated through cleavage after pathogen recognition, informing distant tissues of infection...
  30. Marusek C, Trobaugh N, Flurkey W, Inlow J. Comparative analysis of polyphenol oxidase from plant and fungal species. J Inorg Biochem. 2006;100:108-23 pubmed
  31. Zhu Y, Wang Y, Gorman M, Jiang H, Kanost M. Manduca sexta serpin-3 regulates prophenoloxidase activation in response to infection by inhibiting prophenoloxidase-activating proteinases. J Biol Chem. 2003;278:46556-64 pubmed
    ..Kinetic analysis of PAP-serpin-3 association strongly suggests that serpin-3 is a physiological regulator of the pro-PO activation reaction. ..
  32. Wang Y, Jiang H. Interaction of beta-1,3-glucan with its recognition protein activates hemolymph proteinase 14, an initiation enzyme of the prophenoloxidase activation system in Manduca sexta. J Biol Chem. 2006;281:9271-8 pubmed
    ..These data are consistent with the current model on initiation and regulation of the prophenoloxidase activation cascade upon recognition of pathogen-associated molecular patterns by specific pattern recognition proteins. ..
  33. Massa A, Beecher B, Morris C. Polyphenol oxidase (PPO) in wheat and wild relatives: molecular evidence for a multigene family. Theor Appl Genet. 2007;114:1239-47 pubmed
    ..aestivum cv. Klasic. Nucleotide and structural diversity, together with well-resolved phylogenetic trees, provided molecular evidence to support the hypothesis of a PPO multigene family structure and organization. ..
  34. Li L, Steffens J. Overexpression of polyphenol oxidase in transgenic tomato plants results in enhanced bacterial disease resistance. Planta. 2002;215:239-47 pubmed
    ..These results demonstrate the importance of PPO-mediated phenolic oxidation in restricting plant disease development. ..
  35. Christophides G, Zdobnov E, Barillas Mury C, Birney E, Blandin S, Blass C, et al. Immunity-related genes and gene families in Anopheles gambiae. Science. 2002;298:159-65 pubmed
    ..Representative expression profiles confirm that sequence diversification is accompanied by specific responses to different immune challenges. Alternative RNA splicing may also contribute to expansion of the immune repertoire. ..
  36. Simeone R, Pasqualone A, Clodoveo M, Blanco A. Genetic mapping of polyphenol oxidase in tetraploid wheat. Cell Mol Biol Lett. 2002;7:763-9 pubmed
    ..84. The identification of molecular markers linked to loci controlling the PPO activity may potentially accelerate wheat breeding since the selection of plants can be carried out by genotype rather than phenotype. ..
  37. Dry I, Robinson S. Molecular cloning and characterisation of grape berry polyphenol oxidase. Plant Mol Biol. 1994;26:495-502 pubmed
    ..6 kDa chloroplast transit peptide from the N-terminus and a 16.2 kDa peptide of unknown function from the C-terminus...
  38. Kim M, Baek M, Lee M, Park J, Lee S, Soderhall K, et al. A new easter-type serine protease cleaves a masquerade-like protein during prophenoloxidase activation in Holotrichia diomphalia larvae. J Biol Chem. 2002;277:39999-40004 pubmed
    ..These results indicate that the conversion of Holotrichia proPOs to enzymatically active phenoloxidase is accomplished by PPAF-I, PAF-II, and PPAF-III through a two-step limited proteolysis in the presence of Ca2+. ..
  39. Bocher A, Tirard C, Doums C. Phenotypic plasticity of immune defence linked with foraging activity in the ant Cataglyphis velox. J Evol Biol. 2007;20:2228-34 pubmed
    ..This could result from an adaptive upregulation of the harmful PO (an enzyme potentially leading to autoimmune reactions) only when the risk of infection and wounding is high. ..
  40. Sellés Marchart S, Casado Vela J, Bru Martínez R. Effect of detergents, trypsin and unsaturated fatty acids on latent loquat fruit polyphenol oxidase: basis for the enzyme's activity regulation. Arch Biochem Biophys. 2007;464:295-305 pubmed
    ..Down-regulation of PPO activity by anionic amphiphiles is discussed based on both, the pH profile shift induced upon anionic amphiphile binding and the PPO interaction with negatively charged membranes...
  41. Cerenius L, Soderhall K. The prophenoloxidase-activating system in invertebrates. Immunol Rev. 2004;198:116-26 pubmed
    ..Concomitant with proPO activation, many other immune reactions will be produced, such as the generation of factors with anti-microbial, cytotoxic, opsonic, or encapsulation-promoting activities. ..
  42. Nakayama T, Sato T, Fukui Y, Yonekura Sakakibara K, Hayashi H, Tanaka Y, et al. Specificity analysis and mechanism of aurone synthesis catalyzed by aureusidin synthase, a polyphenol oxidase homolog responsible for flower coloration. FEBS Lett. 2001;499:107-11 pubmed
    ..These results led us to propose a mechanism of aurone synthesis by aureusidin synthase on the basis of known PPO-catalyzed reactions and conclude that the enzyme is a chalcone-specific PPO specialized for aurone biosynthesis. ..
  43. Raman R, Raman H, Johnstone K, Lisle C, Smith A, Martin P, et al. Genetic and in silico comparative mapping of the polyphenol oxidase gene in bread wheat (Triticum aestivum L.). Funct Integr Genomics. 2005;5:185-200 pubmed
    ..Available PPO gene sequences in the National Centre for Biotechnology Information (NCBI) database have revealed that there is a significant molecular diversity at the nucleotide and amino acid level in the wheat PPO genes. ..
  44. Newman S, Eannetta N, Yu H, Prince J, de Vicente M, Tanksley S, et al. Organisation of the tomato polyphenol oxidase gene family. Plant Mol Biol. 1993;21:1035-51 pubmed
    ..Five of the seven PPOs possess divergent DNA sequences in their 5' promoter regions. These flanking sequence differences may regulate the differential expression of PPO genes. ..
  45. Constabel C, Yip L, Patton J, Christopher M. Polyphenol oxidase from hybrid poplar. Cloning and expression in response to wounding and herbivory. Plant Physiol. 2000;124:285-95 pubmed
    ..This wound- and herbivore-induced expression of PPO in hybrid poplar supports the defensive role of this protein against insect pests. ..
  46. Cho M, Moinuddin S, Helms G, Hishiyama S, Eichinger D, Davin L, et al. (+)-Larreatricin hydroxylase, an enantio-specific polyphenol oxidase from the creosote bush (Larrea tridentata). Proc Natl Acad Sci U S A. 2003;100:10641-6 pubmed
    ..This enantio-specificity for a PPO, a representative of a widespread class of enzymes, provides additional insight into their actual physiological roles that hitherto have been difficult to determine...
  47. Prieto H, Utz D, Castro A, Aguirre C, González Agüero M, Valdés H, et al. Browning in Annona cherimola fruit: role of polyphenol oxidase and characterization of a coding sequence of the enzyme. J Agric Food Chem. 2007;55:9208-18 pubmed
    ..Furthermore, the gene is highly divergent from known nucleotide sequences but shows a well conserved protein in terms of its function, deduced structure, and physiological role. ..
  48. Ling E, Yu X. Prophenoloxidase binds to the surface of hemocytes and is involved in hemocyte melanization in Manduca sexta. Insect Biochem Mol Biol. 2005;35:1356-66 pubmed
    ..Our results suggest that activation of hemocyte surface proPO may initiate melanization, leading to the systemic melanization of hemocyte capsules. ..
  49. Wang J, Constabel C. Polyphenol oxidase overexpression in transgenic Populus enhances resistance to herbivory by forest tent caterpillar (Malacosoma disstria). Planta. 2004;220:87-96 pubmed
    ..This activation correlated with partial proteolytic cleavage, suggesting that PPO latency and activation during digestion could be an adaptive and defense-related feature of poplar PPO. ..
  50. Yu X, Jiang H, Wang Y, Kanost M. Nonproteolytic serine proteinase homologs are involved in prophenoloxidase activation in the tobacco hornworm, Manduca sexta. Insect Biochem Mol Biol. 2003;33:197-208 pubmed
    ..SPH, which binds to immulectin-2, may function as a mediator to recruit proPO and PAP to the site of infection. ..
  51. Soderhall K, Cerenius L. Role of the prophenoloxidase-activating system in invertebrate immunity. Curr Opin Immunol. 1998;10:23-8 pubmed
    ..Several components of this system recently have been isolated and their structure determined. ..
  52. Thipyapong P, Hunt M, Steffens J. Antisense downregulation of polyphenol oxidase results in enhanced disease susceptibility. Planta. 2004;220:105-17 pubmed
    ..While PPO B inducibility was the same in both compatible and incompatible interactions, PPO D, E and F were induced to higher levels and with different expression patterns in incompatible interactions. ..
  53. Piao S, Song Y, Kim J, Park S, Park J, Lee B, et al. Crystal structure of a clip-domain serine protease and functional roles of the clip domains. EMBO J. 2005;24:4404-14 pubmed