Catalyzes the formation of dTDP-glucose, from dTTP and glucose 1-phosphate, as well as its pyrophosphorolysis. alpha-D-glucose 1-phosphate + dTTP + H(+) = diphosphate + dTDP-alpha-D-glucose Binds 1 Mg(2+) ion per subunit. Nucleotide-sugar biosynthesis; dTDP-4-acetamido-4,6-dideoxygalactose biosynthesis. Bacterial outer membrane biogenesis; enterobacterial common antigen biosynthesis. Homotetramer. Belongs to the glucose-1-phosphate thymidylyltransferase family.