Involved in the regulation of D-galactonate metabolism (PubMed:211976, PubMed:30455279). Represses the expression of the dgoRKADT operon by binding to two closely spaced inverted repeats in the cis-acting element, which overlap with the D-galactonate responsive dgo promoter (PubMed:30455279). Employs a derepression mechanism using D-galactonate as a specific effector molecule (PubMed:30455279, PubMed:33224125, PubMed:33068046). D-galactonate binds DgoR and induces a conformational change in the protein, which decreases its affinity for DNA and consequently derepresses transcription of the dgoRKADT operon. Homodimer. Part of the dgoRKADT operon, which encodes proteins for the metabolism of D-galactonate (PubMed:211976, PubMed:30455279). Negatively autoregulated (PubMed:30455279). Contains an N-terminal DNA binding region and a C-terminal effector-binding cavity (PubMed:33224125, PubMed:33068046). The C-terminal region also contains a metal binding site (PubMed:33224125). The divalent metal ion is not directly involved in the interaction with DNA, but it plays an important role in interaction with D-galactonate (PubMed:33224125). Deletion of the gene leads to faster growth of E.coli in D-galactonate and results in a considerable increase in the expression of dgo genes.