Purification of a D-hydantoinase using a laboratory-scale Streamline phenyl column as the initial step

A d-hydantoinase from Thermus sp. was overexpressed in Escherichia coli and purified to homogeneity for subsequent crystallization. The purification was performed with hydrophobic interaction chromatography as the capture step followed by anion-exchange chromatography and gel permeation chromatography as intermediate purification and polishing steps, respectively. The hydrophobic interaction step was done in fluidized bed mode in a laboratory-scale Streamline column made from conventional laboratory equipment. The whole purification protocol could be finished within one day. The purified enzyme crystallizes. The crystals are suitable for X-ray protein structure analysis and diffract to at least 2.3 A resolution. Complete data sets have been measured up to 2.6 A resolution. The X-ray structure is currently being solved.