Acid phosphatase localization in the fungus Whetzelinia sclerotiorum

Acid phosphatase was localized by light and electron microscopy in chains of vacuoles in hyphal tip cells of Whetzelinia sclerotiorum. The enzyme was present in these vacuoles whether or not conditions favored extracellular acid phosphatase secretion. Apical vesicles, microbodies, Woronin bodies, and lipid bodies did not contain acid phosphatase. The implications regarding terminology of organelles in filamentous fungi are discussed with special reference to the fungal spherosome concept.