Within the framework of an international project for the sequencing of the entire Bacillus subtilis genome, a 36-kb chromosome segment, which covers the region between the gnt and iol operons, has been cloned and sequenced. This region (36447 bp) contains 33 complete open reading frames (ORFs; genes) including the four gnt genes and one partial gene. A homology search for the products of the 33 complete ORFs revealed significant homology to known proteins in 16 of them such as tetracycline resistance protein ( Clostridium perfringens ), asparagine synthetase ( Arabidopsis thaliana ), aldehyde dehydrogenase ( Pseudomonas oleovorans ), 2,5-dichloro-2,5-cyclohexadiene-1,4-diol dehydrogenase ( P. paucimobilis ), heat shock protein HtpG ( Escherichia coli ), galactose-proton symporter ( E. coli ), auxin-induced protein (common tobacco), glucitol operon repressor ( E. coli ) and methylmalonate-semialdehyde dehydrogenase ( P. aeruginosa ). Unlike the regions we sequenced so far, this region contained two short sequence multiplications: one was a tandem sequence duplication (409 and 410 bp), and the other a triplication consisting of two highly conserved 118-bp tandem sequences preceded by a less conserved similar sequence (129 bp). The reasons for the presence of these sequence multiplications in the gnt to iol region were deduced.