Tellurite-resistance/Dicarboxylate Transporter (TDT) family includes sulfite sensitivity protein (sulfite efflux pump; SSU1)
This family contains the sulfite sensitivity protein (sulfite efflux pump; SSU1) and belongs to the tellurite-resistance/dicarboxylate transporter (TDT) family. The SSU1 gene encodes the sulfite pump required for efficient sulfite efflux. Mutations in the SSU1 gene cause sensitivity to sulfite while overexpression confers heightened resistance to sulfite toxicity. In dematophytes and other filamentous fungi, sulfite is excreted as a reducing agent during keratin degradation; thus sulfite transporters in keratinolytic fungi could be a new target for antifungal drugs in dermatology. The number of genes encoding sulfite efflux pumps in fungal genomes varies from species to species.
Comment:Mutational and structural studies in Haemophilus influenzae TehA (HiTehA) show that this residue plays a crucial role in gating of the anion channel
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