Abstract The tobacco chloroplast gene for the subunit III of proton-translocating ATPase has been sequenced. The gene is located 1709 bp upstream from the α subunit gene and oriented in the same direction. The coding region contains 243 bp (81 codons) and its deduced amino acid sequence is almost identical with those of the wheat and spinach III subunits. The III gene is transcribed independently of the α gene. Five open reading frames were found between the subunit III and α genes.