Expression of human lysosomal beta-hexosaminidase in yeast vacuoles

The yeast Saccharomyces cerevisiae was tested as a recipient for functional expression of a mammalian lysosomal enzyme. The beta chain of human beta-hexosaminidase formed active dimeric enzyme, HexB, in transformants. HexB activity was localized to the vacuole, the yeast counterpart to the lysosome. A simple in situ enzyme assay was developed, which could be useful in expressing other lysosomal cDNAs.