Expression, purification, crystallization and preliminary diffraction studies of the mammalian DAG kinase homologue YegS from Escherichia coli

yegS is a gene encoding a 32 kDa cytosolic protein with unknown function but with strong sequence homology to a family of structurally uncharacterized eukaryotic non-protein kinases: diacylglycerol kinases, sphingosine kinases and ceramide kinases. Here, the overexpression, crystallization and preliminary diffraction analysis of Escherichia coli YegS are reported. The crystals belong to space group P2₁, with unit-cell parameters a = 42.4, b = 166.1, c = 48.5 Å, β = 96.97°. The presence of a dimer in the asymmetric unit was estimated to give a Matthews coefficient (V_M) of 2.5 ų Da⁻¹ and a solvent content of 50.8%(v/v). Single-wavelength diffraction data were collected to a resolution of 1.9 Å using synchrotron radiation.