Crystallization and preliminary X-ray crystallographic studies of Pz peptidase A from Geobacillus collagenovorans MO-1

Abstract

Pz peptidase A is an intracellular M3 metallopeptidase found in the thermophile Geobacillus collagenovorans MO-1 that recognizes collagen-specific tripeptide units (Gly-Pro-Xaa). Pz peptidase A shares common reactions with mammalian thimet oligopeptidase (TOP) and neurolysin, but has extremely low primary sequence identity to these enzymes. In this work, Pz peptidase A was cocrystallized with a phosphine peptide inhibitor (PPI) that selectively inhibits TOP and neurolysin. The crystals belong to space group P2(1), with unit-cell parameters a = 56.38, b = 194.15, c = 59.93 A, beta = 106.22 degrees . This is the first crystallographic study of an M3 family peptidase-PPI complex.

Figure 1

A crystal of the recombinant Pz peptidase A–PPI complex obtained from 12%(w/v) PEG 4000, 0.5 M magnesium acetate and 0.1 M Tris–HCl pH 7.0. The crystal dimensions are about 1.20 × 0.50 × 0.10 mm. The scale bar is 0.5 mm in length.

Figure 2

X-ray diffraction pattern from a crystal of the Pz peptidase A–PPI complex. Diffraction spots are observed to a resolution of 1.8 Å.