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ISRf1, a transposable insertion sequence from Sinorhizobium fredii.

J M Vinardell·F J Ollero·H B Krishnan·M del Rosario Espuny·E Villalobo·S G Pueppke·J E Ruiz-Sainz
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Abstract

Sinorhizobium fredii strain HH103, a nitrogen-fixing bacterial symbiont of plants, contains an insertion sequence (IS) that can transpose into plasmid pMUS248 and activate a promoterless TcR gene that is normally not expressed. We have cloned and characterized this element, which we designate ISRf1. The IS is 1002 bp in length, contains a single 513-bp open reading frame (ORF), is flanked by imperfect 36-bp terminal inverted repeats, and creates 5-bp target duplications. Two copies of ISRf1 are present in the genome of HH103, but it is absent from 12 other Sinorhizobium and Rhizobium strains. The element transposes at a frequency of 2.7 x 10(-6) per generation per cell.

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Amino Acid SequenceBacterial ProteinsBase SequenceDNA Transposable ElementsDNA, BacterialEscherichia coliGene ExpressionGenes, BacterialMolecular Sequence DataRhizobiaceaeJournal ArticleResearch Support, Non-U.S. Gov't

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J M Vinardell, F J Ollero, H B Krishnan, M del Rosario Espuny, E Villalobo, S G Pueppke, J E Ruiz-Sainz. 1997-12-19. ISRf1, a transposable insertion sequence from Sinorhizobium fredii.. https://doi.org/10.1016/s0378-1119(97)00523-4

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