A B. subtvis DNA fragment (1229 bp) known to carry ar gene coding for carbamoyl phosphate synthetase enzyme was cloned in pBB322 and the restriction analysis of this fragment was carried ou? (Kadıkıran, 1988a).The 1229 bp fragment was then cloned in M13mp8 and Mİ 3 mp9 seguencing veeters. Seguencing was carried out by the dideoyy chain termination method. Subcloning was employed to insure the fidelity of seguencing.Of the 1229 bp, 796 bp have been documented while 433 bp streteh of DNA corresponding tc the ieft oi centre on the fragment has not been inciuded due to the further clarifications needed.Restriction site positions on vhe fragment for the restriction enzymes used for restriction analy sis have been refined further.Probable premoter consensuı sequences for -35 promoter up-stream, -10 Pribnow-box, -t-1 start signal sequences have been proposed.