Activating Compound | Comment | Organism | Structure |
---|---|---|---|
aminoguanidine | reactivates enzyme mutant R353 | Homo sapiens | |
guanidine hydrochloride | strongly reactivates enzyme mutant R353 at 0.1-10 mM, approximately 90% of the activity lost in theR535A hcAMPP mutant is regained in the presence of 30 mM guanidine hydrochloride. It has neither an observable rescue effect on wild-type hcAMPP nor on the Y527F mutant | Homo sapiens | |
methylguanidine | reactivates enzyme mutant R353 | Homo sapiens | |
N-ethyl-guanidine | reactivates enzyme mutant R353 | Homo sapiens |
Cloned (Comment) | Organism |
---|---|
gene XPNPEP1, recombinant expression of wild-type and mutant cytosolic aminopeptidases P (hcAMPP, residues M1 to H623), with a thrombin-cleavable N-terminal His-tag in Escherichia coli strain Rosetta (DE3) | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
additional information | kinetic analysis of MnCl2 activation of wild-type, Y527F and R535A hcAMPPs | Homo sapiens |
R535A | site-directed mutagenesis, the mutant enzyme shows reduced kcat and Km compared to the wild-type enzyme. The respective levels of activity restoration are determined to be 86%, 31%, 16%, and 10% for guanidine hydrochloride, methylguanidine, aminoguanidine and N-ethyl-guanidine | Homo sapiens |
Y527F | site-directed mutagenesis, the mutant enzyme shows reduced kcat and Km compared to the wild-type enzyme | Homo sapiens |
Inhibitors | Comment | Organism | Structure |
---|---|---|---|
hydrazine | inactivates wild-type hcAMPP and R535A mutant enzymes | Homo sapiens | |
NaCl | activates the wild-type enzyme at 160 mM, inhibits the enzyme mutant R353A at 160 mM | Homo sapiens |
KM Value [mM] | KM Value Maximum [mM] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
additional information | - |
additional information | Michaelis-Menten steady-state kinetics. Kinetic parameters for R535A hcAMPP measured in the presence and absence of guanidine hydrochloride, overview | Homo sapiens | |
0.144 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 1.0 mM guanidine hydrochloride | Homo sapiens | |
0.163 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 10 mM guanidine hydrochloride | Homo sapiens | |
0.17 | - |
bradykinin | pH 7.5, 37°C, recombinant wild-type enzyme | Homo sapiens | |
0.2 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant Y527F | Homo sapiens | |
0.327 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 0.1 mM guanidine hydrochloride | Homo sapiens | |
0.35 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A | Homo sapiens |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cytosol | - |
Homo sapiens | 5829 | - |
additional information | isoforms of the human enzyme include the cytosolic (hcAMPP) and membrane-bound (hmAMPP) aminopeptidase P, encoded by XPNPEP1 and XPNPEP2 genes, and a third hypothetical isoform thought to be present in mitochondrial and cytosolic localizations | Homo sapiens | - |
- |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mn2+ | activates, required, Km values for Mn2+ are 0.0022 mM for the wild-type enzyme, 0.004 mM for mutant Y527F, and 0.0018 mM for mutant R535A. Kinetic analysis of MnCl2 activation of wild-type, Y527F and R535A hcAMPPs | Homo sapiens | |
additional information | a metalloprotease | Homo sapiens | |
NaCl | activates the wild-type enzyme at 160 mM, inhibits the enzyme mutant R353A at 160 mM | Homo sapiens |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | Q9NQW7 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant His-tagged wild-type and mutant cytosolic isozymes from Escherichia coli strain Rosetta (DE3) by nickel affinity chromatography and ultrafiltration | Homo sapiens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
bradykinin + H2O | i.e. Arg-Pro-Pro-Gly-Phe-Ser-Pro-Phe-Arg | Homo sapiens | des-Arg-bradykinin + Arg | - |
? | |
additional information | aminopeptidase P targets Xaa-Proline peptides for cleavage. Roles of active site residues Tyr527 and Arg535, both residues make significant contributions to the catalytic efficiency, overview | Homo sapiens | ? | - |
? |
Subunits | Comment | Organism |
---|---|---|
? | x * 72000, recombinant enzyme, SDS-PAGE | Homo sapiens |
More | the reported X-ray structure of hcAMPP depicts a homodimer with each subunit containing an N-terminal domain, a middle domain, and a C-terminal catalytic domain, two active site divalent metal ions. Dimerization is mediated by the N-terminal domain and Trp477, and conservation of the key active site residues including Asp415, Asp426, His489, Glu523, Glu537, His395, His485, and His498 | Homo sapiens |
Synonyms | Comment | Organism |
---|---|---|
aminopeptidase P | - |
Homo sapiens |
AMPP | - |
Homo sapiens |
hcAMPP | - |
Homo sapiens |
XPNPEP1 | - |
Homo sapiens |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Homo sapiens |
Temperature Stability Minimum [°C] | Temperature Stability Maximum [°C] | Comment | Organism |
---|---|---|---|
additional information | - |
thermal stability of wild-type and mutant hcAMPPs, overview | Homo sapiens |
Turnover Number Minimum [1/s] | Turnover Number Maximum [1/s] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
0.9 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A | Homo sapiens | |
1.8 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant Y527F | Homo sapiens | |
2 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 0.1 mM guanidine hydrochloride | Homo sapiens | |
3.2 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 1.0 mM guanidine hydrochloride | Homo sapiens | |
8.3 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 10 mM guanidine hydrochloride | Homo sapiens | |
11 | - |
bradykinin | pH 7.5, 37°C, recombinant wild-type enzyme | Homo sapiens |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Homo sapiens |
kcat/KM Value [1/mMs-1] | kcat/KM Value Maximum [1/mMs-1] | Substrate | Comment | Organism | Structure |
---|---|---|---|---|---|
2.57 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A | Homo sapiens | |
6.12 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 0.1 mM guanidine hydrochloride | Homo sapiens | |
9 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant Y527F | Homo sapiens | |
22.22 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 1.0 mM guanidine hydrochloride | Homo sapiens | |
50.92 | - |
bradykinin | pH 7.5, 37°C, recombinant mutant R535A, with 10 mM guanidine hydrochloride | Homo sapiens | |
64.71 | - |
bradykinin | pH 7.5, 37°C, recombinant wild-type enzyme | Homo sapiens |