Partial characterization and identification of a transferrin-like molecule of pathogenic yeast Cryptococcus neoformans

We have partially characterized, purified, and N-terminal amino acid sequenced a protein of approximately 80 kDa from Cryptococcus neoformans, Of the 15 N-terminal amino acids sequenced, 12 are identical to those found in ovotransferrin. Polyclonal antisera raised against ovotransferrin crossreacted with the 80kDa protein. In addition, incorporation of Fe-55 indicated the presence of iron binding by the 80 kDa protein, Because Cryptococcus neoformans does not possess an iron-scavenging ligand, siderophore, we suggest that an alternative transferrin-like molecule (the 80 kDa protein) may play a role in iron uptake by this organism.