Cloned (Comment) | Organism |
---|---|
wild-type benzophenone synthase and enzyme mutants are heterologously expressed as N-terminally His6-tagged proteins in Escherichia coli | Hypericum androsaemum |
Protein Variants | Comment | Organism |
---|---|---|
T135A | inactive enzyme | Hypericum androsaemum |
T135F | mutant functionally resemble the wild-type enzyme, albeit with reduced catalytic activities | Hypericum androsaemum |
T135G | inactive enzyme | Hypericum androsaemum |
T135I | inactive enzyme | Hypericum androsaemum |
T135L | a point mutation in the active site cavity transforms benzophenone synthase into a functional phenylpyrone synthase (PPS). The dramatic change in both substrate and product specificities of benzophenone synthase is rationalized by homology modeling. The mutation may open a new pocket that accommodates the phenyl moiety of the triketide intermediate but limits polyketide elongation to two reactions, resulting in phenylpyrone formation. kcat (substrate: benzoyl-CoA): 0.0086/sec, Km (benzoyl-CoA): 0.001 mM, Km (malonyl-CoA): 8.7 mM. In contrast to the wild-type enzyme, the T135L mutant forms phenylpyrone as a major product and only traces of 2,4,6-trihydroxybenzophenone when incubated with benzoyl-CoA and malonyl-CoA. T135L mutant is almost inactive with 3-hydroxybenzoyl-CoA | Hypericum androsaemum |
T135N | inactive enzyme | Hypericum androsaemum |
T135S | mutant functionally resemble the wild-type enzyme, albeit with reduced catalytic activities | Hypericum androsaemum |
T135V | inactive enzyme | Hypericum androsaemum |
T135Y | inactive enzyme | Hypericum androsaemum |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.001 | - |
benzoyl-CoA | mutant T135L | Hypericum androsaemum | |
0.0086 | - |
benzoyl-CoA | wild-type | Hypericum androsaemum | |
0.0087 | - |
malonyl-CoA | mutant T135L | Hypericum androsaemum | |
0.031 | - |
malonyl-CoA | wild-type | Hypericum androsaemum |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
43000 | - |
SDS-PAGE, molecular weight of mutant T135L | Hypericum androsaemum |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Hypericum androsaemum | - |
- |
- |
Purification (Comment) | Organism |
---|---|
purified on a nickel-nitrilotriacetic acid affinity matrix | Hypericum androsaemum |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
2 malonyl-CoA + benzoyl-CoA | relative activity: 100%, wildtype benzophenone synthase forms 2,4,6-trihydroxybenzophenone as a major product when incubated with benzoyl-CoA and malonyl-CoA, along with small amounts of 6-phenyl-4-hydroxy-2-pyrone | Hypericum androsaemum | 3 CoA + 2,4,6-trihydroxybenzophenone + 2 CO2 | - |
? | |
3 malonyl-CoA + 3-hydroxybenzoyl-CoA | relative activity: 57% | Hypericum androsaemum | 4 CoA + 2,3',4,6-tetrahydroxybenzophenone + 3 CO2 | - |
? | |
3 malonyl-CoA + benzoyl-CoA | relative activity: 100%, wildtype benzophenone synthase forms 2,4,6-trihydroxybenzophenone as a major product when incubated with benzoyl-CoA and malonyl-CoA, along with small amounts of 6-phenyl-4-hydroxy-2-pyrone | Hypericum androsaemum | 4 CoA + 6-phenyl-4-hydroxy-2-pyrone + 3 CO2 | - |
? |
Synonyms | Comment | Organism |
---|---|---|
benzophenone synthase | - |
Hypericum androsaemum |
BPS | - |
Hypericum androsaemum |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Hypericum androsaemum |
Temperature Minimum [°C] | Temperature Maximum [°C] | Comment | Organism |
---|---|---|---|
35 | 40 | optimal temperature | Hypericum androsaemum |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.00685 | - |
benzoyl-CoA | mutant T135L | Hypericum androsaemum | |
0.055 | - |
benzoyl-CoA | wild-type | Hypericum androsaemum |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7 | - |
assay at | Hypericum androsaemum |
7.5 | - |
optimal pH | Hypericum androsaemum |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
6.414 | - |
benzoyl-CoA | wild-type | Hypericum androsaemum | |
6.833 | - |
benzoyl-CoA | mutant T135L | Hypericum androsaemum |