Activating Compound | Comment | Organism | Structure |
---|---|---|---|
SDS | 172% activity at 10 mM | Solanum tuberosum |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
ascorbic acid | effective inhibitor, 99% inhibition at 1 mM | Solanum tuberosum | |
benzoic acid | 9% residual activity at 10 mM | Solanum tuberosum | |
borax | 71% residual activity at 10 mM | Solanum tuberosum | |
CaCl2 | 69% residual activity at 10 mM | Solanum tuberosum | |
Citric acid | 10% residual activity at 10 mM | Solanum tuberosum | |
EDTA | 57% residual activity at 10 mM | Solanum tuberosum | |
L-cysteine | complete inhibition at 1 mM | Solanum tuberosum | |
N-acetyl-L-cysteine | 1% residual activity at 1 mM | Solanum tuberosum | |
NaCl | 84% residual activity at 10 mM | Solanum tuberosum | |
potassium sorbate | 78% residual activity at 10 mM | Solanum tuberosum | |
Sodium metabisulfite | complete inhibition at 1 mM; effective inhibitor, complete inhibition at 1 mM | Solanum tuberosum | |
succinic acid | 35% residual activity at 10 mM | Solanum tuberosum |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | Solanum tuberosum | the partially purified enzyme has both cresolase and catecholase activity. Activity is lower toward monophenols than diphenols | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Solanum tuberosum | - |
cultivar Rooster, rooster potato | - |
Purification (Comment) | Organism |
---|---|
ammonium sulfate precipitation, phenyl Sepharose column chromatography, ion exchange chromatography, and hydroxyapatite column chromatography | Solanum tuberosum |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
additional information | - |
the specific activity of the crude enzyme is 264 units/mg protein, the specific activity of the 64fold purified enzyme is16853 units/mg protein using 50 mM catechol as substrate in 50 mM sodium phosphate buffer, pH 7.0, at 25°C, one unit of PPO activity is defined as the change in absorbance of 0.001 per minute per ml of enzyme | Solanum tuberosum |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
(-)-epicatechin + O2 | 119% activity at 2.5 mM substrate concentration | Solanum tuberosum | ? | - |
? | |
2 catechol + O2 | 100% activity at 10 mM substrate concentration | Solanum tuberosum | 2 1,2-benzoquinone + 2 H2O | - |
? | |
4-methylcatechol + O2 | highest activity, 183% activity at 10 mM substrate concentration | Solanum tuberosum | 4-methyl-1,2-benzoquinone + H2O | - |
? | |
caffeic acid + O2 | 31% activity at 2.5 mM substrate concentration | Solanum tuberosum | caffeoyl quinone + H2O | - |
? | |
DL-DOPA + O2 | 39% activity at 2.5 mM substrate concentration | Solanum tuberosum | dopaquinone + H2O | - |
? | |
L-tyrosine + O2 | very low activity, 6% activity at 2.5 mM substrate concentration | Solanum tuberosum | L-DOPA + H2O | - |
? | |
additional information | the partially purified enzyme has both cresolase and catecholase activity. Activity is lower toward monophenols than diphenols | Solanum tuberosum | ? | - |
? | |
additional information | no activity with ferulic acid and phenol | Solanum tuberosum | ? | - |
? | |
p-cresol + O2 | 20% activity at 2.5 mM substrate concentration | Solanum tuberosum | ? | - |
? | |
pyrogallol + O2 | 92% activity at 10 mM substrate concentration | Solanum tuberosum | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
polyphenol oxidase | - |
Solanum tuberosum |
PPO | - |
Solanum tuberosum |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
- |
Solanum tuberosum |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
20 | 80 | residual activity is higher than 50% after incubation at 20°C for 72 h, at 30°C for 48 h, at 40°C for 24 h, at 50°C for 2 h, and at 60°C for 15 min. Heating at 80°C for 15 min inactivates the enzyme | Solanum tuberosum |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
6 | 6.5 | - |
Solanum tuberosum |
pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|
4.5 | 7.5 | - |
Solanum tuberosum |
pH Stability | pH Stability Maximum | Comment | Organism |
---|---|---|---|
2.5 | 3.5 | the enzyme is most unstable at pH 2.5-3.5 retaining less than 10% of original activity after 2 h | Solanum tuberosum |
6 | 7.5 | more than 50% activity is retained during storage for 72 h at pH 6.0-7.5 | Solanum tuberosum |