The 25.9 kbp region upstream of nprB at 100 degrees-102 degrees on the Bacillus subtilis chromosome was sequenced. This revealed a known gene, degA, which was previously mislocated on the genetic map. A total of 29 putative ORFs were identified including a cluster of three ORFs whose products show clear homology with sulphate adenylyl pathway enzymes and, in addition, 11 ORFs whose products have one or more membrane domains, as indicated by their hydropathy profiles.