Cloning and characterization of the gene encoding a blasticidin S acetyltransferase from Streptoverticillum sp.

A gene (bls) encoding a blasticidin S-acetyltransferase from Streptoverticillum sp. JCM4673 was cloned in the Streptomyces plasmid pIJ702 and expressed in S. lividans 1326. Four of the recombinant plasmids contained a common 1129-bp BclI-PstI DNA fragment, which by subcloning experiments was shown to carry the bls gene. Sequencing of the 1129-bp BclI-PstI fragment indicated that it contains two open reading frames of 408 and 366 nucleotides (nt), both starting with ATG and terminating at TGA triplets. Deletion analysis showed that the correct bls sequence is that of 408 nt, whose deduced amino acid sequence conforms to a polypeptide of Mr 15073. A 175-bp DNA fragment from the 5' region of the bls gene had promoter activity in the promoter-probe plasmid pIJ486.