The Electrophoretic Properties and Some Surface Components of Penicillium Conidia

SUMMARY: Conidia of Penicillium expansum are covered with a surface layer of polyphosphate when grown on a high phosphate medium. The composition of this polyphosphate layer, which appears 2 days after conidial initiation, is dependent on the phosphate content of the growth medium; the layer is absent from conidia grown on a low phosphate medium. The rodlet layer which lies beneath the polyphosphate is free of cutin and does not consist of a unique protein. The amino acid composition of the surface protein is, however, different from that of the total wall protein. The rodlet layer appears to be an integral part of the spore wall. The pH--mobility curves of Penicillium conidia are constant and species-specific when the fungi are grown on defined media.