Cloning of the netropsin resistance genes from Streptomyces flavopersicus NRRL 2820

Streptomyces flavopersicus NRRL 2820 (synonym: Streptomyces netropsis DSM40093) is resistant to the N‐methylpyrrole‐containing oligopeptide antibiotic netropsin. A 9.38 kb DNA‐fragment was isolated from a genomic library of Streptomyces flavopersicus using an Escherichia coli‐Streptomyces lividans shuttle vector which enables S. lividans to grow on netropsin‐containing agar plates. By subcloning, the resistance was conferred to a 5.9 kb Eco RV fragment. DNA sequence analysis of this Eco RV fragment revealed two open reading frames ( netP1 , 1556 bp and netP2 , 1773 bp). The deduced proteins share significant similarity to each other (27% identity) and to the large family to ABC‐type multidrug resistance proteins. In each protein a conserved transmembrane and ATP binding domain was identified. Deletion analysis showed that both proteins are necessary for netropsin resistance indicating that the proteins form a heterodimeric ABC‐transporter exporting netropsin. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)