1UOO

Prolyl oligopeptidase from porcine brain, S554A mutant with bound peptide ligand GLY-PHE-ARG-PRO

Summary for 1UOO

• Entry DOI: 10.2210/pdb1uoo/pdb
• Related: 1E5T 1E8M 1E8N 1H2W 1H2X 1H2Y 1H2Z 1O6F 1O6G 1QFM 1QFS 1UOQ
• Descriptor: PROLYL ENDOPEPTIDASE, PEPTIDE LIGAND GLY-PHE-ARG-PRO, GLYCEROL, ... (4 entities in total)
• Functional Keywords: hydrolase, prolyl oligopeptidase, amnesia, alpha/ beta-hydrolase, beta-propeller, serine protease
• Biological source: SUS SCROFA (PIG); More
• Total number of polymer chains: 2
• Total formula weight: 81416.99

Authors

Rea, D.,Fulop, V. (deposition date: 2003-09-22, release date: 2003-10-02, Last modification date: 2023-12-13)

Primary citation

Szeltner, Z.,Rea, D.,Renner, V.,Juliano, L.,Fulop, V.,Polgar, L.
Electrostatic Environment at the Active Site of Prolyl Oligopeptidase is Highly Influential During Substrate Binding
J.Biol.Chem., 278:48786-, 2003

PubMed Abstract: The positive electrostatic environment of the active site of prolyl oligopeptidase was investigated by using substrates with glutamic acid at positions P2, P3, P4, and P5, respectively. The different substrates gave various pH rate profiles. The pKa values extracted from the curves are apparent parameters, presumably affected by the nearby charged residues, and do not reflect the ionization of a simple catalytic histidine as found in the classic serine peptidases like chymotrypsin and subtilisin. The temperature dependence of kcat/Km did not produce linear Arrhenius plots, indicating different changes in the individual rate constants with the increase in temperature. This rendered it possible to calculate these constants, i.e. the formation (k1) and decomposition (k-1) of the enzyme-substrate complex and the acylation constant (k2), as well as the corresponding activation energies. The results have revealed the relationship between the complex Michaelis parameters and the individual rate constants. Structure determination of the enzyme-substrate complexes has shown that the different substrates display a uniform binding mode. None of the glutamic acids interacts with a charged group. We conclude that the specific rate constant is controlled by k1 rather than k2 and that the charged residues from the substrate and the enzyme can markedly affect the formation but not the structure of the enzyme-substrate complexes.

PubMed: 14514675
DOI: 10.1074/JBC.M309555200

Experimental method

X-RAY DIFFRACTION (2.35 Å)