Presence of carnitine acetyltransferase in peroxisomes and in mitochondria of oleic acid-grown Saccharomyces cerevisiae

Abstract Paracoccidiodes brasiliensis , the agent of paracoccidioidomycosis, when grown in a synthetic medium, expresses at the cell surface of both yeast and mycelial forms acidic glycoconjugates containing N -acetlyneuraminic acid units. Sialic acids were extracted using mild hydrolytic conditions, and were identified by thin-layer and gas chromatography, standard colorimetry, reaction with periodate-resorcinol and mass spectrometry. Their surface location was inferred from fluorescent-lectin ( Limulus polyphemus agglutinin) binding to whole cells abrogated by previous treatment with neuraminidase. Expression of sialic acids on virulent yeast forms of P. brasiliensis (3.7 × 10⁶ residues per cell) may inhibit fungal phagocytosis during early infection, when the immunological response is still being built up.