EC Number | Inhibitors | Comment | Organism | Structure |
---|---|---|---|---|
1.14.18.1 | ascorbic acid | 50% and 78% inhibition at 1 mM for the cv. Narince samples from 2006 and 2007, respectively | Vitis vinifera | |
1.14.18.1 | L-cysteine | 52% and 76% inhibition at 1 mM for the cv. Narince samples from 2006 and 2007, respectively | Vitis vinifera | |
1.14.18.1 | additional information | no inhibition by citric acid. The mode of action of inhibitors differs from each other. Ascorbic acid and metabisulfite are reducing agents, which can either reduce o-quinones to colourless diphenols or react irreversibly with o-quinones to form stable colourless | Vitis vinifera | |
1.14.18.1 | Sodium metabisulfite | 49% and 74% inhibition at 1 mM for the cv. Narince samples from 2006 and 2007, respectively | Vitis vinifera |
EC Number | Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|---|
1.14.18.1 | chloroplast | - |
Vitis vinifera | 9507 | - |
1.14.18.1 | thylakoid membrane | - |
Vitis vinifera | 42651 | - |
EC Number | Metals/Ions | Comment | Organism | Structure |
---|---|---|---|---|
1.14.18.1 | Cu2+ | a copper-containing enzyme | Vitis vinifera |
EC Number | Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
1.14.18.1 | additional information | Vitis vinifera | polyphenol oxidase is a copper-containing enzyme that, in the presence of oxygen, catalyses the hydroxylation of monophenols to o-diphenols (cresolase activity) and the oxidation of o-diphenols to their corresponding o-quinones (catecholase activity) | ? | - |
? |
EC Number | Organism | UniProt | Comment | Textmining |
---|---|---|---|---|
1.14.18.1 | Vitis vinifera | - |
cv. Narince, harvested from the Anatolia plateau south of the mountains near the Black Sea shores, Tokat Province | - |
EC Number | Source Tissue | Comment | Organism | Textmining |
---|---|---|---|---|
1.14.18.1 | berry | - |
Vitis vinifera | - |
1.14.18.1 | fruit | - |
Vitis vinifera | - |
EC Number | Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|---|
1.14.18.1 | 2 4-methylcatechol + O2 | - |
Vitis vinifera | 2 4-methyl-1,2-benzoquinone + 2 H2O | - |
? | |
1.14.18.1 | 2 catechol + O2 | - |
Vitis vinifera | 2 1,2-benzoquinone + 2 H2O | - |
? | |
1.14.18.1 | caffeic acid + O2 | - |
Vitis vinifera | ? + 2 H2O | - |
? | |
1.14.18.1 | additional information | polyphenol oxidase is a copper-containing enzyme that, in the presence of oxygen, catalyses the hydroxylation of monophenols to o-diphenols (cresolase activity) and the oxidation of o-diphenols to their corresponding o-quinones (catecholase activity) | Vitis vinifera | ? | - |
? | |
1.14.18.1 | additional information | substrate specificity in descendent order of activity from Vmax/Km: caffeic acid, 4-methylcatechol, catechol, pyrogallol | Vitis vinifera | ? | - |
? | |
1.14.18.1 | pyrogallol + O2 | - |
Vitis vinifera | ? + 2 H2O | - |
? |
EC Number | Synonyms | Comment | Organism |
---|---|---|---|
1.14.18.1 | polyphenol oxidase | - |
Vitis vinifera |
1.14.18.1 | PPO | - |
Vitis vinifera |
EC Number | Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|---|
1.14.18.1 | 45 | - |
- |
Vitis vinifera |
EC Number | Temperature Minimum [°C] | Temperature Maximum [°C] | Comment | Organism |
---|---|---|---|---|
1.14.18.1 | 20 | 70 | over 50% of maximal activity within this range | Vitis vinifera |
EC Number | Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|---|
1.14.18.1 | 70 | - |
half-lives of the cv. Narince samples from 2006 and 2007 are 57 min and 28 min, respectively | Vitis vinifera |
1.14.18.1 | 75 | - |
half-lives of the cv. Narince samples from 2006 and 2007 are 28 min and 13 min, respectively | Vitis vinifera |
1.14.18.1 | 80 | - |
half-lives of the cv. Narince samples from 2006 and 2007 are 13 min and 4 min, respectively | Vitis vinifera |
EC Number | pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|---|
1.14.18.1 | 5.5 | - |
- |
Vitis vinifera |
EC Number | pH Minimum | pH Maximum | Comment | Organism |
---|---|---|---|---|
1.14.18.1 | 3.4 | 6.3 | over 50% of maximal activity within this range | Vitis vinifera |
EC Number | General Information | Comment | Organism |
---|---|---|---|
1.14.18.1 | physiological function | in plants, PPO is predominantly located in the chloroplast thylakoid membranes, and its phenolic substrates are mainly located in the vacuoles but, following any treatment that damages the cells, the enzyme and substrates may come into contact, leading to rapid oxidation of the phenols | Vitis vinifera |