Crystallization and preliminary X-ray characterization of phosphoglucose isomerase from Mycobacterium tuberculosis H37Rv

Abstract

Phosphoglucose isomerase is a ubiquitous enzyme that catalyzes the isomerization of D-glucopyranose-6-phosphate to D-fructofuranose-6-phosphate. The present investigation reports the expression, purification, crystallization and preliminary crystallographic studies of the phosphoglucose isomerase from Mycobacterium tuberculosis H37Rv, which shares 46% sequence identity with that of its human host. The recombinant protein, which was prepared using an Escherichia coli expression system, was crystallized by the hanging-drop vapour-diffusion method. The crystals diffracted to a resolution of 2.8 A and belonged to the orthorhombic space group I2(1)2(1)2(1), with unit-cell parameters a = 109.0, b = 119.8, c = 138.9 A.

Figure 1

A bipyramidal crystal of PGI from M. tuberculosis with dimensions of 0.3 × 0.2 × 0.15 mm.

Figure 2

A diffraction pattern of a PGI crystal collected at beamline ID23-1 at the ESRF Grenoble, France with exposure times adjusted to avoid incomplete data arising from overloading.