Activating Compound | Comment | Organism | Structure |
---|---|---|---|
Polyphosphate | addition of inorganic polyphosphate (PPin) inhibits or activates glycerol kinase due to the complexation of PPin with Mg2+ that shifts Mg2+ to ATP molar ratio below or to the optimum level | Cellulomonas sp. |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
ADP | competitive inhibition versus ATP | Cellulomonas sp. | |
AMP | competitive inhibition versus ATP | Cellulomonas sp. | |
Ca2+ | inhibition by Ca2+ due to the formation of enzymatically inactive Ca-ATP complexes. The Ca2+ salt of ATP is not an appropriate substrate for glycerol kinase. Ca2+ must be removed by ion exchange pretreatment from enzyme preparations | Cellulomonas sp. | |
Mg2+ | essentially required for activity, maximum activity at the optimum Mg2+ to ATP molar ratio of [0.12-0.3]. Subsequent increase of Mg2+ to ATP molar ratio higher than the values in the optimum region suppresses the enzyme activity to a non-zero asymptotic value | Cellulomonas sp. | |
additional information | phosphate (Pi) and sn-glycerol-3-phosphate (sn-G3P) do not inhibit glycerol kinase | Cellulomonas sp. | |
Polyphosphate | addition of inorganic polyphosphate (PPin) inhibits or activates glycerol kinase due to the complexation of polyphosphate with Mg2+ that shifts Mg2+ to ATP molar ratio below or to the optimum level | Cellulomonas sp. |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | the enzyme exhibits two-step kinetics as a function of ATP at a fixed Mg2+ concentration due to the formation of multiple Mg-ATP complexes at different Mg2+ to ATP molar ratio. The active site of glycerol kinase shows different catalytic property with respect to different Mg-ATP complexes. Glycerol kinase exhibits high affinity (low Km) and less activity (low kcat) for complexes with a stoichiometric or over-stoichiometric constitution like Mg2+-ATP. On the other hand, the enzyme shows less affinity (high Km) and high activity (high kcat) for unsaturated complexes like [Mg(ATP)2]6-. Detailed kinetic analysis of glycerol kinase as a function of Mg2+ to ATP molar ratio, overview. The enzyme exhibits Michaelis-Menten kinetics. The two-step kinetic behavior of glycerol kinase as function of ATP at a fixed Mg2+ concentration can rather be explained due to the various Mg-ATP complexes formed at different Mg2+/ATP molar ratios that bind to the active site. In consequence, different Km and kcat values are determined with respect to the different Mg-ATP complexes | Cellulomonas sp. | |
0.012 | - |
glycerol | pH 8.5, 30°C | Cellulomonas sp. | |
0.09 | - |
ATP | ATP at 21 mM Mg2+, pH 8.5, 30°C | Cellulomonas sp. | |
0.12 | - |
ATP | ATP at 10.5 mM Mg2+, pH 8.5, 30°C | Cellulomonas sp. | |
0.28 | - |
ATP | ATP at 1.5 mM Mg2+, pH 8.5, 30°C | Cellulomonas sp. | |
1.7 | - |
ATP | ATP at 10.5 mM Mg2+, pH 8.5, 30°C | Cellulomonas sp. | |
1.7 | - |
ATP | ATP at 21 mM Mg2+, pH 8.5, 30°C | Cellulomonas sp. | |
2.061 | - |
ATP | Mg2+/ATP molar ratio constant at 0.3, pH 8.5, 30°C | Cellulomonas sp. |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | essentially required for activity, maximum activity at the optimum Mg2+ to ATP molar ratio of [0.12-0.3]. Subsequent increase of Mg2+ to ATP molar ratio higher than the values in the optimum region suppresses the enzyme activity to a non-zero asymptotic value. The enzyme exhibits two-step kinetics as a function of ATP at a fixed Mg2+ concentration due to the formation of multiple Mg-ATP complexes at different Mg2+ to ATP molar ratio. The interaction of Mg2+ and ATP generates Mg-ATP complexes of various physical and chemical features in which the product composition depends on Mg2+ to ATP molar ratio among other factors such as pH, temperature, availability of other polyvalent chelating anions as well as cations and their concentration | Cellulomonas sp. |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + glycerol | Cellulomonas sp. | - |
ADP + sn-glycerol 3-phosphate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Cellulomonas sp. | - |
- |
- |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
commercial preparation | - |
Cellulomonas sp. | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
ATP + glycerol | - |
Cellulomonas sp. | ADP + sn-glycerol 3-phosphate | - |
? | |
additional information | the enzyme exhibits two-step kinetics as a function of ATP at a fixed Mg2+ concentration due to the formation of multiple Mg-ATP complexes at different Mg2+ to ATP molar ratio. The interaction of Mg2+ and ATP generates Mg-ATP complexes of various physical and chemical features in which the product composition depends on Mg2+ to ATP molar ratio among other factors such as pH, temperature, availability of other polyvalent chelating anions, as well as cations and their concentration. The Ca2+ salt of ATP is not an appropriate substrate for glycerol kinase | Cellulomonas sp. | ? | - |
- |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Cellulomonas sp. |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8.5 | - |
assay at | Cellulomonas sp. |
General Information | Comment | Organism |
---|---|---|
additional information | detailed kinetic analysis of glycerol kinase as a function of Mg2+ to ATP molar ratio, and multinuclear NMR study of the Mg-ATP complex formation is described in order to elucidate the effect of Mg2+ in modifying the physical and chemical features of ATP, and mechanistic elucidation of the effect of Mg-ATP interaction on the catalytic properties of glycerol kinase, overview | Cellulomonas sp. |