Catalyzes the adenylation by ATP of the carboxyl group of the C-terminal glycine of sulfur carrier protein ThiS. [sulfur-carrier protein ThiS]-C-terminal Gly-Gly + ATP + H(+) = [sulfur-carrier protein ThiS]-C-terminal Gly-Gly-AMP + diphosphate Binds 1 zinc ion per subunit. Cofactor biosynthesis; thiamine diphosphate biosynthesis. Homodimer. Belongs to the HesA/MoeB/ThiF family. Truncated N-terminus.