GPI-linked hyphal surface heme-binding protein involved in heme-iron utilization (PubMed:15306022, PubMed:17042757, PubMed:18466294, PubMed:21205162, PubMed:25275454, PubMed:27617569). Heme transfer occurs between PGA7, RBT5 and CSA2 supporting a model in which the 3 CFEM proteins cooperate in a heme-acquisition system and form a cross-cell wall heme-transfer cascade (PubMed:15306022, PubMed:17042757, PubMed:18466294, PubMed:21205162, PubMed:25275454, PubMed:27617569). The ability to acquire iron from host tissues is a major virulence factor of pathogenic microorganisms. Required for biofilm formation (PubMed:15306022, PubMed:17042757, PubMed:18466294, PubMed:21205162, PubMed:25275454). Interacts with PGA7. Found anchored in the cell membrane as well as a covalently-linked GPI-modified cell wall protein (GPI-CWP). Induced by iron starvation, hypoxia, amphotericin B, and during hyphal growth. Repressed by ketoconazole and caspofungin. Regulated by BCR1, HOG1, SFU1, TUP1, and UPC2. The CFEM domain is involved in heme-binding and contains 8 cysteines and is found in proteins from several pathogenic fungi, including both human and plant pathogens (PubMed:12633989, PubMed:22145027, PubMed:25275454). The CFEM domain adopts a novel helical-basket fold that consists of six alpha-helices, and is uniquely stabilized by four disulfide bonds formed by its 8 signature cysteines (By similarity). The GPI-anchor is attached to the protein in the endoplasmic reticulum and serves to target the protein to the cell surface. There, the glucosamine-inositol phospholipid moiety is cleaved off and the GPI-modified mannoprotein is covalently attached via its lipidless GPI glycan remnant to the 1,6-beta-glucan of the outer cell wall layer. Mannosylated. Leads to defects in hemin and hemoglobin utilization as sole source of iron. Belongs to the RBT5 family.