High frequency transposition of the Tn5 derivative Tn5493 in Streptomyces lividans.

The mini-Tn5 derivative transposon Tn5493 transposes at a frequency as high as 3% in the Gram-positive bacterium Streptomyces lividans. The use of a thiostrepton-resistance gene and a temperature-sensitive delivery system carrying the transposase gene allows an easy selection for stable transposition events. Insertions into the S. lividans genome seem to be fairly random, as shown by Southern blot and pulsed-field gel electrophoresis (PFGE). Transpositions were easily mapped by PFGE using the restriction sites of rare-cutting enzymes present in the transposon. Because of its characteristics, Tn5493 is a promising tool for genetic and molecular analysis and manipulation of the antibiotic-producing streptomycetes.