N-acetylglucosamine (GlcNAc) kinase; requires a divalent cation and a broad range of NTPs as phosphoryl donor to generate GlcNAc-6-phosphate, a substrate for glycan biosynthesis; promotes UDP-GlcNAc biosynthesis a precursor for chitin production; phylogenically distinct from known GlcNAc kinases and hexokinases; transcript is upregulated during sporulation and the unfolded protein response; contains a hexokinase-like ATPase domain; non-essential gene