Fig. 1.

Biochemical characterization of SaYqeK. (A) SDS-PAGE analysis of recombinant SaYqeK purification. M, molecular weight standards; a, crude extract; b, Ni-NTA pool. (B) Gel filtration chromatography of Ni-NTA pool (solid line) and standard proteins (dotted line). (C) UV spectral analysis of the Ni-NTA pool (solid line) and gel filtration pool (dashed line). (D) HPLC analysis of the acid-soluble fraction of the Ni-NTA pool (red) and ADP standard (blue). (E) SaYqeK ligand screening by thermal shift analysis. Ligands were tested at 5 μM concentration. For ease of viewing, bars are colored with different shades of gray. (F) HPLC profile at 260 nm of the reaction mixture of SaYqeK (50 μg/ml) at 0 and 20 min of incubation in the presence of 0.2 mM Ap₄A. A standard ADP profile is also shown (std).