Lipid composition of Paracoccidioides brasiliensis: comparison between the yeast and mycelial forms.

The total lipid extracted from the yeast form of Paracoccidioides brasiliensis was twice as much as from the mycelial form. In both morphological forms neutral lipids were predominant and triglycerides were the greatest single component in the extracts. Relative percentage of phospholipid was higher in Y form than in M form. Phosphatidylcholine was predominant in the former and phosphatidylethanolamine in the latter. Diphosphatidylglycerol was the most unsaturated lipid in both the forms, and in the Y form it was the only individual class of lipid that contained a greater percentage of linoleic than oleic acid. Otherwise, the lipids of Y form, both neutral and polar, were characterized by a greater percentage of oleic acid and those of the M form by the predominance of linoleic acid. Differential distribution of phosphatidylcholine, phosphatidylethanolamine, sterol, oleic and linoleic acid in Y and M forms is interpreted to suggest a possible role of cellular lipid composition in the dimorphic behaviour of P. brasiliensis.