IS<Emphasis Type="Italic">Ppy1</Emphasis>, a novel mobile element of the ancient <Emphasis Type="Italic">Psychrobacter maritimus</Emphasis> permafrost strain: Translocations in <Emphasis Type="Italic">Escherichia coli</Emphasis> K-12 cells and formation of composite transposons

It was shown that IS element ISPpy1 isolated earlier in the permafrost strain Psychrobacter maritimus MR29-12 has a high level of functional activity in cells of the heterologous host Escherichia coli K-12. ISPpy1 can be translocated in E. coli cells by itself and mobilize adjacent genes and can also form composite transposons flanked by two copies of this element. Apart from translocations between different plasmids, the composite ISPpy1-containing transposon Tn5080a is capable of translocation from the plasmid into the E. coli chromosome with high frequency and from the chromosome into the plasmid. Among products of Tn5080a transposition into plasmid R388, simple insertions were predominantly formed together with cointegrates. Upon mobilization of adjacent genes with the use of one ISPpy1 copy, only cointegrates arise.