In addition to its GlcNAc kinase activity, it wasrecently shownthat NAGK can phosphorylate MDP to generate MDP-6-phosphate in responseto bacterial infection.19 We thereforetested the ability of wt-NAGK, pS76-NAGK, and ppS76-NAGK to utilizeMDP as a substrate. The gene discussed is NAGK; the disease is bacterial infectious disease.