Squalene metabolism of the sterol auxotroph Lagenidium giganteum was s
tudied and compared with that of the positive control Lagenidium calli
nectes. Application of experimentally derived precautions ensured both
the stability and the purity of squalene during incubations. Under th
ese conditions mycelia of L. giganteum converted squalene to squalene
oxide and to a sterol-like compound. Cell-free and microsomal preparat
ions also converted squalene to the oxide, which was identified by thi
n layer chromatography with five different solvent systems, by co-chro
matography with authentic oxide, and by conversion to the glycol. Supp
orting evidence for the production of squalene oxide was obtained by g
as-liquid chromatography, high performance liquid chromatography, and
autoradiography. The squalene oxide produced was identified by mass sp
ectrometry.