Expression, purification and X-ray characterization of residues 18-230 from the pneumococcal histidine triad protein A (PhtA) from Streptococcus pneumoniae

Abstract

A fragment of the Streptococcus pneumoniae PhtA gene product (residues 18-230) was cloned and overexpressed in Escherichia coli. The purified protein was crystallized using the sitting-drop vapour-diffusion technique. Crystals belong to the monoclinic space group C2, with unit-cell parameters a = 62.19, b = 35.9, c = 72.54 A, beta = 90.01 degrees. The crystals diffract X-rays to beyond 1.2 A resolution.