Properties and developmental regulation of an alpha-d-galactosidase from Dictyostelium discoideum.

An alpha-D-galactosidase was detected in cells of the cellular slime mould, Dictyostelium discoideum, at all stages of development. Its specific activity was highest during early development (interphase), and this accumulation of enzyme appears to require protein synthesis de novo. Its subcellular distribution differs from that of other D. discoideum glycosidases, since most activity was recovered in the soluble fraction. No evidence was obtained for more than one isoenzymic form after subjection of extracts to electrophoresis and various chromatographic procedures. It is excreted from the cell during development, but no evidence was found for an extracellular function for the enzyme.