Expression, purification, crystallization and preliminary X-ray analysis of Rv3117, a probable thiosulfate sulfurtransferase (CysA3) from Mycobacterium tuberculosis

MtbCysA3, a probable rhodanese-like thiosulfate sulfurtransferase, has been expressed, purified and crystallized. Preliminary X-ray analysis shows a dimer in the asymmetric unit. The gene product of open reading frame Rv3117 from Mycobacterium tuberculosis (Mtb) strain H37Rv is annotated as encoding a probable rhodanese-like thiosulfate sulfurtransferase (MtbCysA3). MtbCysA3 was expressed and purified and then crystallized using the sitting-drop vapour-diffusion method. X-ray diffraction data were collected and processed to a maximum resolution of 2.5 Å. The crystals belong to the monoclinic space group P2₁, with unit-cell parameters a = 38.86, b = 91.43, c = 83.57 Å, β = 96.6°. Preliminary diffraction data shows that two molecules are present in the asymmetric unit; this corresponds to a V_M of 2.4 ų Da⁻¹