A large operon-type structure has been located between the gltA and ci
tB loci on the Bacillus subtilis chromosome. On the basis of the analy
sis of the 25 kb sequenced so far, it potentially encodes at least thr
ee large proteins which contain structural motifs associated with the
subunits of all characterized peptide synthases. The amino acid recogn
ition specificity of this new peptide synthase is discussed in the lig
ht of sequence homology with other synthases.