Catalyzes the oxidation of L-galactonate to D-tagaturonate. Required for growth on L-galactonate as the sole carbon source. In vitro, can also use L-gulonate. L-galactonate + NAD(+) = H(+) + keto-D-tagaturonate + NADH Binds 2 Zn(2+) ions per subunit. Inhibited by EDTA. kcat is 0.51 sec(-1) with L-galactonate. Optimum pH is 8.0. Highly up-regulated during growth on L-galactonate. Cells lacking this gene fail to grow on L-galactonate as sole carbon source. Belongs to the zinc-containing alcohol dehydrogenase family. Extended N-terminus.