Activating Compound | Comment | Organism | Structure |
---|---|---|---|
vitamin K | dependent on | Homo sapiens |
Cloned (Comment) | Organism |
---|---|
expression of wild-type and mutant enzymes in HEK-293 cells | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
E186A | site-directed mutagenesis, the fIXa mutant exhibits normal activity towards a fIXa-specific chromogenic substrate in the presence of Ca2+ with no obvious requirement for Na+ in the reaction, the mutant interacts with factor VIIIa with near normal affinity and catalyzes the activation of factor X in the intrinsic Xase complex with a normal catalytic efficiency | Homo sapiens |
H185A | site-directed mutagenesis, the fIXa mutant exhibits normal activity towards a fIXa-specific chromogenic substrate in the presence of Ca2+ with no obvious requirement for Na+ in the reaction, the mutant interacts with factor VIIIa with near normal affinity and catalyzes the activation of factor X in the intrinsic Xase complex with a normal catalytic efficiency | Homo sapiens |
R188A | site-directed mutagenesis, the fIXa mutant exhibits normal activity towards a fIXa-specific chromogenic substrate in the presence of Ca2+ with no obvious requirement for Na+ in the reaction, the mutant interacts with factor VIIIa with near normal affinity and catalyzes the activation of factor X in the intrinsic Xase complex with a normal catalytic efficiency | Homo sapiens |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
EDTA | complete inhibition at 20 mM | Homo sapiens |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | steady-state kinetics of wild-type and mutant enzymes n presence or absence of NaCl | Homo sapiens | |
2.2 | - |
CH3SO2-D-Leu-Gly-Arg-4-nitroanilide | pH 7.5, 37°C, recombinant wild-type enzyme, in absence of NaCl | Homo sapiens | |
2.2 | - |
CH3SO2-D-Leu-Gly-Arg-4-nitroanilide | pH 7.5, 37°C, recombinant wild-type enzyme, in presence of 0.2 M NaCl | Homo sapiens |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Ca2+ | activates | Homo sapiens | |
Na+ | no requirement for Na+ in presence of Ca2+, can partially substite for Ca2+ | Homo sapiens |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
factor X + H2O | Homo sapiens | - |
activated factor X + ? | - |
? | |
additional information | Homo sapiens | the enzyme is a trypsin-like serine protease in plasma that binds to its cofactor factor VIIIa on negatively charged membrane surfaces in the presence of Ca2+, i.e. intrinsic Xase, to activate factor X to factor Xa in the clotting cascade, factor IXa plays an essential role in hemostasis and its deficiency is associated with the life threatening disease, hemophilia B | ? | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | P00740 | - |
- |
Posttranslational Modification | Comment | Organism |
---|---|---|
proteolytic modification | proteolytic cleavages at two peptide bonds after Arg145 and Arg180 by either one of two physiological activators, the factor VIIa-tissue factor complex or factor XIa, leads to removal of the activation peptide and conversion of fIX to a fully active enzyme consisting of a light and a heavy chain held together by a single disulfie bond | Homo sapiens |
Purification (Comment) | Organism |
---|---|
recombinant wild-type and mutant enzymes from HEK-293 cells by immunoaffinity and anion exchange chromatogaphy | Homo sapiens |
Source Tissue | Comment | Organism | Textmining |
---|---|---|---|
plasma | factor IX circulates in plasma as a single chain inactive zymogen | Homo sapiens | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
CH3SO2-D-Leu-Gly-Arg-4-nitroanilide + H2O | amidolytic activity | Homo sapiens | ? | - |
? | |
factor X + H2O | - |
Homo sapiens | activated factor X + ? | - |
? | |
factor X + H2O | factor IXa acts as part of phosphocholine/phosphoserine vesicles interacting with factor VIIIa in the intrinsic tenase complex | Homo sapiens | activated factor X + ? | - |
? | |
additional information | the enzyme is a trypsin-like serine protease in plasma that binds to its cofactor factor VIIIa on negatively charged membrane surfaces in the presence of Ca2+, i.e. intrinsic Xase, to activate factor X to factor Xa in the clotting cascade, factor IXa plays an essential role in hemostasis and its deficiency is associated with the life threatening disease, hemophilia B | Homo sapiens | ? | - |
? | |
additional information | the loop harboring the S1 specficity site contains the residues His185, Glu186, and Arg188, which, incontrast to other coagulation factor proteases, e.g. unlike thrombin and factor Xa, do not play a functional role in modulating the catalytic function of fIXa in the intrinsic Xase complex, overview | Homo sapiens | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | the fully active enzyme consists of a light and a heavy chain held together by a single disulfie bond | Homo sapiens |
Synonyms | Comment | Organism |
---|---|---|
factor IXa | - |
Homo sapiens |
FIXa | - |
Homo sapiens |
intrinsic Xase | - |
Homo sapiens |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Homo sapiens |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
18.5 | - |
CH3SO2-D-Leu-Gly-Arg-4-nitroanilide | pH 7.5, 37°C, recombinant wild-type enzyme, in absence of NaCl | Homo sapiens | |
20.2 | - |
CH3SO2-D-Leu-Gly-Arg-4-nitroanilide | pH 7.5, 37°C, recombinant wild-type enzyme, in presence of 0.2 M NaCl | Homo sapiens |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Homo sapiens |