KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | Michaelis-Menten kinetics.The regenerated enzyme displays similar Km and kcat values to the purified enzyme, with only a small increase in the Km for L-serine | Sphingomonas paucimobilis | |
0.0356 | - |
palmitoyl-CoA | recombinant wild-type enzyme, pH 7.5, 25°C | Sphingomonas paucimobilis | |
1.6 | - |
L-serine | recombinant wild-type enzyme, pH 7.5, 25°C | Sphingomonas paucimobilis |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
palmitoyl-CoA + L-serine | Sphingomonas paucimobilis | - |
CoA + 3-dehydro-D-sphinganine + CO2 | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Sphingomonas paucimobilis | Q93UV0 | - |
- |
Reaction | Comment | Organism | Reaction ID |
---|---|---|---|
palmitoyl-CoA + L-serine = CoA + 3-dehydro-D-sphinganine + CO2 | the reaction proceeds via several intermediate states, the pyridoxal 5'-phosphate cofactor binds to an active site lysine residue as an internal aldimine/Schiffs base (I). The L-serine displaces the lysine residue (Lys265) to form the PLP-L-serine external aldimine (II). Deprotonation of II gives a carbanion/quinonoid species (III) which condenses in a Claisen-like manner with the acyl-CoA thioester substrate to form a PLP-beta-keto acid, which then decarboxylates to generate the PLP-KDS product quinonoid (IV). This then reprotonates to form PLP-KDS aldimine (V) which is finally displaced by Lys265. The step releasing CoA and CO2 and producing the quinonoid intermediate species is irreversible. Interaction between the hydroxyl group of the L-serine substrate and the 5'-phosphate group of pyridoxal 5'-phosphate occurs in the formation of the external aldimine II, overview | Sphingomonas paucimobilis |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | no activity with L-phosphoserine | Sphingomonas paucimobilis | ? | - |
? | |
palmitoyl-CoA + L-serine | - |
Sphingomonas paucimobilis | CoA + 3-dehydro-D-sphinganine + CO2 | - |
? | |
palmitoyl-CoA + L-serine | interaction between the hydroxyl group of the L-serine substrate and the 5'-phosphate group of pyridoxal 5'-phosphate. This interaction is important for substrate specificity and optimal catalytic efficiency | Sphingomonas paucimobilis | CoA + 3-dehydro-D-sphinganine + CO2 | - |
? |
Synonyms | Comment | Organism |
---|---|---|
serine palmitoyltransferase | - |
Sphingomonas paucimobilis |
SPT | - |
Sphingomonas paucimobilis |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
25 | - |
assay at | Sphingomonas paucimobilis |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
1.54 | - |
L-serine | recombinant wild-type enzyme, pH 7.5, 25°C | Sphingomonas paucimobilis |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Sphingomonas paucimobilis |
Cofactor | Comment | Organism | Structure |
---|---|---|---|
pyridoxal 5'-phosphate | dependent on, bound by lysine 265 residue, interaction between the hydroxyl group of the L-serine substrate and the 5'-phosphate group of pyridoxal 5'-phosphate. This interaction is important for substrate specificity and optimal catalytic efficiency | Sphingomonas paucimobilis |
General Information | Comment | Organism |
---|---|---|
evolution | the enzyme belongs to the PLP-superfamily and a member of the alpha-oxoamine synthase family (AOS, fold type I) | Sphingomonas paucimobilis |
additional information | the interaction between the hydroxyl group of the L-serine substrate and the 5'-phosphate group of pyridoxal 5'-phosphate is important for substrate specificity and optimal catalytic efficiency. Structure of the PLP-L-serine external aldimine intermediate of the enzyme, PDB ID 2W8J, overview | Sphingomonas paucimobilis |
physiological function | the enzyme is required for de novo sphingolipid biosynthesis | Sphingomonas paucimobilis |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.9625 | - |
L-serine | recombinant wild-type enzyme, pH 7.5, 25°C | Sphingomonas paucimobilis |