Secreted heme-binding protein involved in the utilization of iron from human hemoglobin during hyphal growth (PubMed:24796871, PubMed:27617569). May also play a role in non-hemoglobin iron utilization (PubMed:24796871). 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:27617569). The ability to acquire iron from host tissues is a major virulence factor of pathogenic microorganisms (PubMed:24796871). Homodimer (PubMed:27617569). The possibility of a transient honotrimer assembly of the holo protein is not ruled out (PubMed:27617569). Expression is induced during hyphal growth, by ketoconazole, and nitric oxide. Expression is also regulated by RIM101, TSA1, HAP43 and BCR1. 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:27617569). 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 (PubMed:27617569). Leads to defects in hemoglobin utilization as sole source of iron. CSA2 could be used as a new diagnostic marker of Candida albicans infection. Belongs to the RBT5 family.