Represses the expression of the aconitase gene acn and its own expression, in an iron-responsive manner. Binds to the inverted repeat element present in the upstream region of acn (Rv1475c)-Rv1474c operon. Preferentially binds to major groove of the DNA. Binding to DNA is abolished in the presence of high concentration of iron. Specifically binds to tetracycline, which leads to a conformational change in the structure of the protein and inhibits the DNA binding activity. Homodimer. Negatively autoregulated. Its association with indispensable iron homeostasis makes Rv1474c an attractive target for designing novel anti-mycobacterials.