GENE ORGANIZATION IN THE BLEOMYCIN-RESISTANCE REGION OF THE PRODUCER ORGANISM STREPTOMYCES-VERTICILLUS

A nucleotide sequence of 7 kb is reported, encompassing two bleomycin- resistance (Bm(R)-encoding) genes and five other open reading frames ( ORFs) from the Bm-producing organism Streptomyces verticillus ATCC 150 03. The deduced ORFs, in sequence order, encode for (i) a protein homo logous to an amino-acid dioxygenase; (ii) BlmA, the Bm(R)-binding prot ein described by Sugiyama et al. [Gene 151 (1994) 11-16]; (iii) a prod uct containing three copies of a sequence homologous to the ankyrin re peat; (iv) a product lacking homology to any of the sequences in the P rotein Identification Resource database (PIR), release 37; (v) BlmB, t he Bm(R) acetyltransferase described by Sugiyama et al. (1994); (vi) a n unidentified protein which augmented resistance determined by ORF2 ( BlmA); (vii) a member of the ATP-binding cassette (ABC) family of tran sport proteins. Predicted translational frameshifts in the -1 frame oc cur at the junctions between ORF3 and ORF4, ORF4 and ORF5, and ORF6 an d ORF7. Sequences homologous to ORF2 and ORF3 were identified in the g enome of the producer organism for the related antibiotic phleomycin.