Optimized transformation, overexpression and purification of S100A10.

As a member of the S100 protein family, S100A10, has already been purified. However, its purity, or even yield, have often not beenreported in the literature. To facilitate future biophysical experiments with S100A10, we aimed to obtain it at a purity of at least 95% in a reasonably large amount. Here, we report optimized conditions for the transformation, overexpression and purification of the protein. We obtained a purity of 97% and performed stability studies by circular dichroism. Our data confirmed that the S100A10 obtained is suitable for experiments to be performed at room temperature up to several days. METHOD SUMMARY The GST-S100A10 gene carried by the pGEX-6P-1 vector was overexpressed in transformed Escherichia coli and purified by glutathione S-transferase (GST) affinity chromatography. The GST tag was cleaved by PreScission protease, excess glutathione was removed by centrifugal filtration and buffer exchange and the GST tag removed by a second GST affinity chromatography. S100A10 was identified by LC/MS-MS and the stability of the secondary structure was analyzed by circular dichroism at different temperatures.