Bifunctional enzyme involved in the synthesis of UDP-N-acetylglucosamine (UDP-GlcNAc) and UDP-N-acetylgalactosamine (UDP-GalNAc). It has multiple amino-sugar-1-phosphate acetyltransferase activities, including glucosamine-1-phosphate (GlcN-1-P) acetyltransferase and galactosamine-1-phosphate (GalN-1-P) acetyltransferase activities, and multiple sugar-1-phosphate nucleotidylyltransferase activities, including N-acetylglucosamine-1-phosphate (GlcNAc-1-P) uridyltransferase and N-acetylgalactosamine-1-phosphate (GalNAc-1-P) uridyltransferase activities (PubMed:15598657, PubMed:20400541, PubMed:25567746). Also catalyzes the formation of dTDP-glucose from dTTP and glucose-1-phosphate (Glc-1-P), and the reverse reaction, which produces dTTP from dTDP-glucose and diphosphate (PubMed:15598657). Can also catalyze the formation of UDP-glucose from UTP and glucose-1-phosphate (PubMed:27864169, PubMed:30291121). alpha-D-glucose 1-phosphate + dTTP + H(+) = diphosphate + dTDP-alpha-D-glucose alpha-D-glucose 1-phosphate + H(+) + UTP = diphosphate + UDP-alpha-D-glucose H(+) + N-acetyl-alpha-D-galactosamine 1-phosphate + UTP = diphosphate + UDP-N-acetyl-alpha-D-galactosamine H(+) + N-acetyl-alpha-D-glucosamine 1-phosphate + UTP = diphosphate + UDP-N-acetyl-alpha-D-glucosamine acetyl-CoA + alpha-D-galactosamine 1-phosphate = CoA + H(+) + N-acetyl-alpha-D-galactosamine 1-phosphate acetyl-CoA + alpha-D-glucosamine 1-phosphate = CoA + H(+) + N-acetyl-alpha-D-glucosamine 1-phosphate Can also use Mg(2+) and Zn(2+), with lower efficiency. Important for nucleotidylyltransferase activity. GlcN-1-P acetyltransferase activity is inhibited by divalent cations. GalN-1-P acetyltransferase activity is enhanced by Co(2+), Mg(2+) and Ca(2+), but inhibited by Zn(2+) or Mn(2+). kcat is 69.7 sec(-1) for GalN-1-P acetyltransferase activity. kcat is 123.2 sec(-1) for GlcN-1-P acetyltransferase activity. Optimum pH is 8.5 for glucose-1-phosphate thymidylyltransferase activity. Optimum temperature is 95 degrees Celsius for glucose-1-phosphate thymidylyltransferase activity. Nucleotide-sugar biosynthesis; UDP-N-acetyl-alpha-D-glucosamine biosynthesis; N-acetyl-alpha-D-glucosamine 1-phosphate from alpha-D-glucosamine 6-phosphate (route II): step 2/2. Nucleotide-sugar biosynthesis; UDP-N-acetyl-alpha-D-glucosamine biosynthesis; UDP-N-acetyl-alpha-D-glucosamine from N-acetyl-alpha-D-glucosamine 1-phosphate: step 1/1. Homotrimer. The C-terminal domain is essential for the formation of the trimer and the high thermostability of the entire protein. The C-terminal 11 residues are important for GalN-1-P AcTase activity, but they have an inhibitory effect on the GlcN-1-P AcTase activity. In the N-terminal section; belongs to the N-acetylglucosamine-1-phosphate uridyltransferase family. In the C-terminal section; belongs to the transferase hexapeptide repeat family.