Cell surface-bound protein that functions in the copper-accumulation pathway shared by the CUF1-dependent copper transporter CTR1 (PubMed:31932719). Binds Cu(2+) with an estimated 1:1 stoichiometry and might serve as an extracellular copper ligand (PubMed:31932719). FRE4 and FRE7 metalloreductases probably function together with CTR1 and BIM1 to liberate the Cu(2+) bound to the BIM1 copper-binding site for subsequent import of Cu(+) into the cell by CTR1, via the reduction of BIM1-bound Cu(2+) to Cu(+) to reduce binding affinity for BIM1 but increase affinity for CTR1 (Probable). Facilitates copper acquisition in the brain of mammalian hosts and acts as a copper-dependent virulence trait in fungal meningitis (PubMed:31932719). While BIM1 plays a critical role in cryptococcal meningitis, at least in part through its role in copper acquisition, it could play additional roles during copper limitation or as a means to invade and colonize host tissues in the brain, by compromising host carbohydrate integrity via its lytic polysaccharide monooxygenase (LPMO) activity, which has still to be determined (Probable). Interacts with the CUF1-dependent copper transporter CTR1. Expression is highly induced in response to copper limitation by the copper-specific chelator bathocuproine disulfonic acid (BCS) (PubMed:31932719). The BIM1 promoter harbors three conserved Cu-responsive elements (CuRE), which are critical for CUF1 binding and activation under copper-limiting conditions, beginning at positions -239, -268 and -516 (PubMed:31932719). Consistent with their presence, binding of the CUF1 copper-sensing transcription factor to the BIM1 promoter is strongly induced under copper-limiting conditions and expression of BIM1 under these conditions is CUF1-dependent (PubMed:31932719). Exhibits growth defect on copper-deficient medium ot in the presence of the copper-specific chelator bathocuproine disulfonic acid (BCS) (PubMed:31932719). Shows a reduction in cell-associated copper, in the enzymatic activity of Cu/Zn superoxide dismutase, in laccase-dependent melanin production and in the accumulation of cellular iron, a well-established copper-dependent process (PubMed:31932719). Does not affect virulence in an A/J mouse pulmonary infection model (PubMed:31932719).