Description:
<jats:p>The 24 kDa fragment of DNA gyrase B from <jats:italic>Staphylococcus aureus</jats:italic> was expressed in <jats:italic>Escherichia coli</jats:italic> and purified for crystallization. Crystals of the wild-type protein grew in the presence of cyclothialidine but proved difficult to reproduce. In order to improve the crystallization, the flexible regions of the protein were deleted by mutagenesis. The mutant proteins were analyzed by differential scanning calorimetry and the most stable mutants produced crystals. It was possible to reproducibly grow in the microbatch system single well defined crystals which belonged to the space group <jats:italic>C</jats:italic>2 and diffracted isotropically to approximately 2 Å resolution.</jats:p>