Expression and functional analysis of a predicted atsg arylsulphatase identified from mycobacterium tuberculosis genomic data

Sulphatase family enzymes hydrolyse the sulphate ester, found on the pathogens cell surface and playing an important role for host-pathogen interaction. The AtsG, homologue of arylsulphatase, predicted in the Mycobacterium tuberculosis genomic data, was successfully expressed in Escherichia coli. The recombinant AtsG protein exhibited hydrolysis of para-nitrophenyl sulphate and para-nitrocatechol sulphate, and binding affinity to the heparin-sepharose resin. This is the first report of molecular evidence for an arylsulphatase activity of the AtsG protein. The maximum activity was detected at pH 8.0 and 37°C. As EDTA completely inhibited this activity, a divalent cation was required for the activity.