Localization of dipeptidyl aminopeptidase yscIV in the plasma membrane of Saccharomyces cerevisiae.

The subcellular distribution of dipeptidyl aminopeptidase activity was studied in protoplast lysates of Saccharomyces cerevisiae that were virtually free from vacuolar contamination. Dipeptidyl aminopeptidase yscIV, the STE13 gene product, was found to be associated with plasma membrane vesicles after sucrose gradient isopycnic centrifugation. Another dipeptidyl aminopeptidase activity, not yet fully characterized, was localized in a microvesicular population co-sedimenting with chitosomes.