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. Carbohydrate biosynthesis; dTDP-L-rhamnose biosynthesis. Capsule biogenesis; capsule polysaccharide biosynthesis. Belongs to the glucose-1-phosphate thymidylyltransferase family.