Characterization of a recombinant N-acetylgalactosamine-6-sulfate sulfatase produced in E. coli for enzyme replacement therapy of Morquio A disease

► rGALNS was extracellularly produced in Escherichia coli BL21. ► Purified enzyme showed a 0.21 U mg−1 activity and a production yield of 0.78 mg L−1. ► rGALNS showed similar temperature and pH stability profiles to mammalian GALNS proteins. ► rGALNS was not taken up by culture cells. ► Glycosylations seem to be necessary for protein uptake but not for stability.