Cell wall-anchored surface receptor that extracts heme from oxidized metHb to enable growth on hemoglobin as a sole iron source. Rapidly extracts heme from hemoglobin and transfers it to IsdA or IsdC, which then relays it to the membrane transporter/IsdEF for internalization. Promotes also resistance to hydrogen peroxide and killing by neutrophils. Interacts with host HBA; this interaction allows heme extraction as iron source. Interacts with IsdA. Anchored to the cell wall by sortase A. Repressed by fur in the presence of iron. Belongs to the IsdB family.