What is the function of prolyl oligopeptidase?
Prolyl oligopeptidase is a large cytosolic enzyme that belongs to a new class of serine peptidases. The enzyme is involved in the maturation and degradation of peptide hormones and neuropeptides, which relate to the induction of amnesia.
Is prolyl oligopeptidase a serine peptidase?
Although prolyl oligopeptidase was recognized as a serine peptidase as early as 1977 [3], it is commonly found to be activated by thiol compounds, and for a time the thiol-dependent activity was recognized by a separate EC number, EC 3.4.22.18.
What is prolyl oligopeptidase (POP)?
Prolyl oligopeptidase (POP) is a member of the S9 family of serine proteases that cleaves small peptides at peptide bonds that follow proline residues ( Coetzer et al., 2008 ). The POP gene is located on chromosome 6q22 in humans and on chromosome 10B2 B3 in mice, both containing 15 exons each ( García-Horsman et al., 2007 ).
What does the noncatalytic domain of prolyl oligopeptidase look like?
The noncatalytic domain of prolyl oligopeptidase looks less regular and less compact than other propellers, e.g., the β subunit of G protein ( Figure 4 ). Consequently, these two domains could not be tightly superimposed; the rms deviation was 2.66 Å for 148 fitted Cα atoms of the propeller (with 17.6% sequence identity for that region).
What is wrong with oligopeptidase activity?
The most intriguing problem of oligopeptidase activity concerns the access of substrate to the active site, which is hidden in a large cavity at the interface of the catalytic and β-propeller domains ( Figure 2 and Figure 6 ).
What’s new in prolyl oligopeptidase catalysis?
Prolyl oligopeptidase catalysis. Reactions with thiono substrates reveal substrateinduced conformational change to be the rate-limiting step. New prolyl endopeptidase inhibitors. Improved Fourier coefficients for maps using phases from partial structures with errors.
How many blades does prolyl oligopeptidase have?
The C-terminal catalytic domain of prolyl oligopeptidase is covalently linked to an unusual seven-bladed propeller. Unlike other β propellers, the “Velcro” is not closed between the first and last blades of prolyl oligopeptidase.