Catalyzes the conversion of 2-amino-2-deoxy-D-gluconate (GlcNA) to 2-keto-3-deoxy-D-gluconic acid (KDGA) and ammonia. 2-amino-2-deoxy-D-gluconate = 2-dehydro-3-deoxy-D-gluconate + NH4(+) The active site is a redox-active disulfide bond. Belongs to the class-II pyridine nucleotide-disulfide oxidoreductase family. Extended C-terminus. The sequence does not corresponds to the one published in PubMed:12686150.