Cell wall-anchored surface receptor that participates in the extraction of heme from oxidized methemoglobin/metHb to enable growth on hemoglobin as a sole iron source. Receives heme from IsdB and transfers it to IsdC. Also plays a role in the inhibition of host immune response. Protects S.aureus against the bactericidal protease activity of apolactoferrin. Decreases bacterial cellular hydrophobicity, which renders S.aureus resistant to bactericidal human skin fatty acids as well as to beta-defensins and cathelicidin. Also binds fibronectin and chains B-beta and gamma of fibrinogen, promoting clumping of S.aureus with fibrinogen. Involved in adherence of S.aureus to human desquamated nasal epithelial cells and is required for nasal colonization 