Expression of mouse Gal,ß14GlcNAc α2,6-sialyl-transferase in an insoluble form in Escherichia coli and partial renaturation

Mouse Galßl,4GlcNAc α2,6-sialyltransferase was produced in an insoluble form in Escherichia coli cells harboring expression plasmids. The insoluble protein was solubilized with 8 M urea and diluted for renaturation of the enzyme. The substrate specificity and kinetic parameters, except for the specific activity, of the renatured enzyme were similar to those of the enzyme obtained from rat liver. These results suggest that a bacterial expression system is a potentially powerful tool for the large scale production of sialyltransferases and for elucidating the molecular mechanisms of sialyltransferases.