Cloned (Comment) | Organism |
---|---|
gene TgTCEB1, recombinant expression of the wild-type enzyme in Escherichia coli strain Rosetta 2 (DE3)/pET28a | Tulipa gesneriana |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | Michaelis-Menten kinetics | Tulipa gesneriana | |
1.2 | - |
1,6-tuliposide D | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
2.2 | - |
tuliposide F | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
3 | - |
6-tuliposide A | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
6.8 | - |
6-tuliposide B | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
chloroplast | - |
Tulipa gesneriana | 9507 | - |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
6-tuliposide B | Tulipa gesneriana | - |
tulipalin B + D-glucose | - |
? | |
tuliposide F | Tulipa gesneriana | - |
(3R)-3-hydroxy-2-methylidenecyclopentan-1-one + 1-tuliposide A | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Tulipa gesneriana | I4DST8 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant wild-type enzyme from Escherichia coli strain Rosetta 2 (DE3)/pET28a | Tulipa gesneriana |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
leaf | - |
Tulipa gesneriana | - |
pollen | - |
Tulipa gesneriana | - |
root | - |
Tulipa gesneriana | - |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
5.3 | - |
recombinant enzyme, substrate 6-tuliposide A, pH 6.5, 22°C | Tulipa gesneriana |
32 | - |
recombinant enzyme, substrate 1,6-tuliposide D, pH 6.5, 22°C | Tulipa gesneriana |
440 | - |
recombinant enzyme, substrate tuliposide F, pH 6.5, 22°C | Tulipa gesneriana |
740 | - |
recombinant enzyme, substrate 6-tuliposide B, pH 6.5, 22°C | Tulipa gesneriana |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
1,6-tuliposide D | i.e. PosD, the enzyme catalyzes intramolecular transesterification, PosD is a 1,6-diacyl-glucose type of Pos, the enzyme shows 4.3% activity with PosD compared to 6-PosB | Tulipa gesneriana | tulipalin A + 1-tuliposide A | - |
? | |
6-tuliposide A | i.e. 6-PosA, a monoacyl-glucose type of Pos, the enzyme catalyzes intramolecular transesterification, the enzyme shows 0.72% activity with 6-PosA compared to 6-PosB | Tulipa gesneriana | tulipalin A + D-glucose | - |
? | |
6-tuliposide B | - |
Tulipa gesneriana | tulipalin B + D-glucose | - |
? | |
6-tuliposide B | i.e. 6-PosB, a monoacyl-glucose type of Pos, the enzyme catalyzes intramolecular transesterification, best substrate | Tulipa gesneriana | tulipalin B + D-glucose | - |
? | |
additional information | 6-PosB is chemically labile, and they can be spontaneously converted to PaB in neutral to weakly basic conditions in vitro. 1-Tuliposide A (1-PosA) is no substrate | Tulipa gesneriana | ? | - |
? | |
tuliposide F | - |
Tulipa gesneriana | (3R)-3-hydroxy-2-methylidenecyclopentan-1-one + 1-tuliposide A | - |
? | |
tuliposide F | i.e. PosF, the enzyme catalyzes intramolecular transesterification, PosF is a 1,6-diacyl-glucose type of Pos, the enzyme shows 59% activity with PosF compared to 6-PosB, the configuration at the C-3' position of the substrate PosF is S-form | Tulipa gesneriana | (3R)-3-hydroxy-2-methylidenecyclopentan-1-one + 1-tuliposide A | - |
? |
Subunits | Comment | Organism |
---|---|---|
homodimer | - |
Tulipa gesneriana |
Synonyms | Comment | Organism |
---|---|---|
Pos-converting enzyme | - |
Tulipa gesneriana |
PosB-converting enzyme | - |
Tulipa gesneriana |
TCEB | - |
Tulipa gesneriana |
TgTCEB1 | - |
Tulipa gesneriana |
tuliposide B converting enzyme | - |
Tulipa gesneriana |
tuliposide-converting enzyme | - |
Tulipa gesneriana |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
22 | - |
assay at room temperature | Tulipa gesneriana |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
8.7 | - |
6-tuliposide A | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
35 | - |
1,6-tuliposide D | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
580 | - |
tuliposide F | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
2000 | - |
6-tuliposide B | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
6.5 | - |
assay at | Tulipa gesneriana |
General Information | Comment | Organism |
---|---|---|
physiological function | tuliposide A converting enzyme (TCEA) and tuliposide B-converting enzyme (TCEB) catalyze intramolecular transesterification of 6-PosA and 6-PosB to form the corresponding lactones, PaA and PaB, respectively, and D-glucose. 6-PosA and 6-PosB serve as precursors of the corresponding alpha-methylene-gamma-butyrolactones, tulipalins A (PaA) and B (PaB), respectively, which are formed from the acyl group at the C-6 position. The 1alpha- and 1beta-anomers exist for 6-PosA/6-PosB and both anomers serve as substrates for TCEs. TCEA and TCEB catalyze the formation of PaA/1-PosA and PaB/1-PosA from PosD and PosF, respectively, by acting on the 6-acyl group of PosD and PosF. Neither enzyme acts on the 1-acyl group of PosD, PosF, or 1-PosA. Although intact tulip tissues constitutively accumulate large amounts of 6-Pos, biologically active PaA and PaB are far less abundant and are sometimes barely detectable, PaA and PaB are hardly detectable in intact plants. PaA and PaB respectively show antifungal and antibacterial activities, they are considered to be key secondary metabolites in the chemical defense of tulip, while 6-PosA and 6-PosB are considered to be storage forms of PaA and PaB, respectively. Enzyme TCEB shows lower overall activity than enzyme TCEA | Tulipa gesneriana |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
2.9 | - |
6-tuliposide A | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
29 | - |
1,6-tuliposide D | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
260 | - |
tuliposide F | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana | |
290 | - |
6-tuliposide B | recombinant enzyme, pH 6.5, 22°C | Tulipa gesneriana |