Activating Compound | Comment | Organism | Structure |
---|---|---|---|
additional information | enzymatic activity may be induced in the reaction mixture by the addition of a ionic detergent, e.g. SDS | Agaricus bisporus | |
SDS | activates at 2 mM | Agaricus bisporus |
Cloned (Comment) | Organism |
---|---|
Agaricus bisporus possesses genes coding for six different tyrosinases (AbPPO1-AbPPO6), full-length gene AbPPO4 (1-565) DNA and amino acid sequence determination and analysis, recombinant expression of N-terminally GST-tagged tyrosinase 4 from gene AbPPO4 containing 23 mutations in Escherichia coli as latent enzyme | Agaricus bisporus |
Crystallization (Comment) | Organism |
---|---|
purified recombinant detagged latent tyrosinase, X-ray diffraction structure determination and analysis. In contrast to the crystals obtained with the enzyme isolated from the natural source which contains two different chains in the asymmetric unit (one latent and one active protein) and does only form in the presence of sodium hexatungstotellurate(VI) (Na6[TeW6O24] x 22 H2O), the recombinant enzyme forms crystals containing exclusively the latent tyrosinase. The latent chain of AbPPO4 isolated from Agaricus bisporu, PDB ID 4OUA, chain B, is aligned with the heterologously produced protein, PDB ID 5M6B, chain B | Agaricus bisporus |
Protein Variants | Comment | Organism |
---|---|---|
additional information | mutations relative to GQ354802 mRNA for the reference sequence for AbPPO4, Uniprot ID C7FF05 : C21T, T168C, T306C, T362C (V121A), T483C, A504C, G536A (S179N), A540C, T717C, T735C, G1089A, C1104T, C1131G, G1218A, C1359T, T1449C, C1458T, A1521G, C1650T, T1686C, T1704C, G1717A (V573I), G1783A (A595T) in the wild-type AbPPO4 and C21T, G97A (V33I), G133T (A45S), T168C, G301A (V101I), G324C, T362C (V121A), T483C, A504C, G536A (S179N), A540C, G563A (R188K), C618T, C620G (A207G), T171C, T735C, G1089A, C1131G, T1172A & C1173A (L391Q), G1783A (A595T) in the mutant AbPPO4DELTA(A436-A580). Construction of a truncated enzyme mutant encoding only the main domain of the tyrosinase up to residue S383, which does not exhibit any tyrosinase activity | Agaricus bisporus |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
3.14 | - |
L-tyrosine | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
4.65 | - |
catechol | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
9.53 | - |
tyramine | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
12.5 | - |
phenol | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
15.2 | - |
dopamine | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
26.1 | - |
L-Dopa | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Cu2+ | a type III copper-containing metalloenzyme | Agaricus bisporus |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
2 L-dopa + O2 | Agaricus bisporus | - |
2 dopaquinone + 2 H2O | - |
? | |
L-tyrosine + O2 | Agaricus bisporus | - |
dopaquinone + H2O | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Agaricus bisporus | C7FF05 | mushroom tyrosinase describes a mixture of isoenzymes containing a number of enzymatic side-activities | - |
Posttranslational Modification | Comment | Organism |
---|---|---|
proteolytic modification | the latent recombinant tyrosinase 4 enzyme can be activated by limited proteolysis with proteinase K, which cleaves the polypeptide chain after K382, only one The latent enzyme can amino acid before the main in-vivo activation site. Activation by proteinase K is more efficient compared to activation by trypsin | Agaricus bisporus |
Purification (Comment) | Organism |
---|---|
recombinant GST-tagged enzyme from Escherichia coli by glutathione affinity chromatography, followed by tag cleavage through specific protease HRV 3 C | Agaricus bisporus |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
commercial preparation | mushroom tyrosinase | Agaricus bisporus | - |
fruiting body | tyrosinase 4 | Agaricus bisporus | - |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
1.22 | - |
purified recombinant enzyme, substrate L-tyrosine, pH 6.8, 25°C | Agaricus bisporus |
Storage Stability | Organism |
---|---|
4°C, purified recombinant detagged enzyme, after 1 year of storage in 10 mM HEPES, pH 7.5, the enzyme is still active | Agaricus bisporus |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
2 L-dopa + O2 | - |
Agaricus bisporus | 2 dopaquinone + 2 H2O | - |
? | |
catechol + O2 | reaction of EC 1.10.3.1 | Agaricus bisporus | ? | - |
? | |
dopamine + O2 | - |
Agaricus bisporus | ? | - |
? | |
L-tyrosine + O2 | - |
Agaricus bisporus | dopaquinone + H2O | - |
? | |
additional information | the proteolytically activated mushroom tyrosinase shows over 50% of its maximal activity in the range of pH 5-10 and accepts a wide range of substrates including mono- and diphenols, flavonols and chalcones. The activated AbPPO4 catalyzes both reactions observed for tyrosinase. The catechol oxidase activity proceeds typically with a rate two orders of magnitude faster than the hydroxylation and oxidation of monophenols. Of the tested substrates the enzyme exhibits the highest affinity and the lowest reaction rate for L-tyrosine. Activated AbPPO4 discriminates between enantiomers of tyrosine showing pronounced differences in the rate of the tyrosinase reaction. For tyrosine 1 mM of the L-enantiomer is converted at a rate of 1.22 U/mg, which is 2.58times faster than the rate on D-tyrosine. A slight increase in enantioselectivity is seen for the methyl ester of tyrosine | Agaricus bisporus | ? | - |
? | |
phenol + O2 | - |
Agaricus bisporus | ? | - |
? | |
tyramine + O2 | - |
Agaricus bisporus | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
? | x * 52000, recombinant wild-type enzyme, SDS-PAGE | Agaricus bisporus |
Synonyms | Comment | Organism |
---|---|---|
AbPPO4 | - |
Agaricus bisporus |
mushroom tyrosinase | - |
Agaricus bisporus |
polyphenol oxidase 4 | UniProt | Agaricus bisporus |
tyrosinase 4 | - |
Agaricus bisporus |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Agaricus bisporus |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
3.77 | - |
L-tyrosine | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
11.3 | - |
phenol | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
15.6 | - |
tyramine | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
1080 | - |
catechol | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
1810 | - |
L-Dopa | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus | |
2540 | - |
dopamine | pH 6.8, 25°C, recombinant enzyme | Agaricus bisporus |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
6.8 | - |
assay at | Agaricus bisporus |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
5 | 10 | the proteolytically activated mushroom tyrosinase shows over 50% of its maximal activity in the range of pH 5-10 and accepts a wide range of substrates including mono- and diphenols, flavonols and chalcones | Agaricus bisporus |
pH Stability | pH Stability Maximum | Comment | Organism |
---|---|---|---|
5 | 10 | in the pH-range from pH 5-10 the enzyme retains more than 50% of its activity | Agaricus bisporus |
General Information | Comment | Organism |
---|---|---|
physiological function | tyrosinases are an ubiquitous group of copper-containing metalloenzymes that hydroxylate and oxidize phenolic molecules. Tyrosinase catalyzes the o-hydroxylation of monophenols (EC 1.14.18.1) and the oxidation of o-diphenols (cf. EC 1.10.3.1) | Agaricus bisporus |