FIG. 3.

BT NRPS operon. (A) Construction of a supercontig from two contigs linked by a mate pair. Contig 1 and contig 2 share a mate pair from a clone. The contigs are ordered and arranged to form a supercontig, which contains the sequences of contig 1 and contig 2, which are separated by an unsequenced gap region. (B) Region sequenced in this work and location of 10 ORFs found in the region. Six ORFs (btA through btF) encode the BT NRPS subunits. (C) Domain organization of the BT NRPS subunits. The predicted amino acid substrate specificity of each module is indicated in each A-domain. (D) Phylogenetic tree for a multiple-sequence alignment of all 13 binding pocket constituents described in Table 3. The putative specificity was assigned using the partial BT1583 sequence. The binding pockets of A-domains that supposedly activate the same or similar substrate cluster together.