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 degrees C. As EDTA completely inhibited this activity, a divalent cation was required for the activity.