title: Transposase interaction with the β sliding clamp: effects on insertion sequence proliferation and transposition rate.
abstract: Insertion sequences (ISs) are ubiquitous and abundant mobile genetic elements in prokaryotic genomes. ISs often encode only one protein, the transposase, which catalyzes their transposition. Recent studies have shown that transposases of many different IS families interact with the β sliding clamp, a DNA replication factor of the host. However, it was unclear to what extent this interaction limits or favors the ability of ISs to colonize a chromosome from a phylogenetically-distant organism, or if the strength of this interaction affects the transposition rate. Here we describe the proliferation of a member of the IS1634 family in Acidiphilium over ~600 generations of cultured growth. We demonstrate that the purified transposase binds to the β sliding clamp of Acidiphilium, Leptospirillum and E. coli. Further, we also demonstrate that the Acidiphilium IS1634 transposase binds to the archaeal sliding clamp (PCNA) from Methanosarcina, and that the transposase encoded by Methanosarcina IS1634 binds to Acidiphilium β. Finally, we demonstrate that increasing the strength of the interaction between β and transposase results in a higher transposition rate in vivo. Our results suggest that the interaction could determine the potential of ISs to be mobilized in bacterial populations and also their ability to proliferate within chromosomes.
authors: Centro de Astrobiología (INTA-CSIC), Ctra. de Ajalvir, Km. 4, Torrejón de Ardoz, 28850 Madrid, Spain.
authors: Héctor
authors: H
authors: Díaz-Maldonado
authors: Centro de Astrobiología (INTA-CSIC), Ctra. de Ajalvir, Km. 4, Torrejón de Ardoz, 28850 Madrid, Spain.
authors: Manuel J
authors: MJ
authors: Gómez
authors: Centro de Astrobiología (INTA-CSIC), Ctra. de Ajalvir, Km. 4, Torrejón de Ardoz, 28850 Madrid, Spain.
authors: Mercedes
authors: M
authors: Moreno-Paz
authors: Centro de Astrobiología (INTA-CSIC), Ctra. de Ajalvir, Km. 4, Torrejón de Ardoz, 28850 Madrid, Spain.
authors: Patxi
authors: P
authors: San Martín-Úriz
authors: Centro de Astrobiología (INTA-CSIC), Ctra. de Ajalvir, Km. 4, Torrejón de Ardoz, 28850 Madrid, Spain.|Centro de Biología Molecular Severo Ochoa (UAM-CSIC), 28049 Madrid, Spain.
authors: Ricardo
authors: R
authors: Amils
authors: Centro de Astrobiología (INTA-CSIC), Ctra. de Ajalvir, Km. 4, Torrejón de Ardoz, 28850 Madrid, Spain.
authors: Víctor
authors: V
authors: Parro
authors: Centro de Astrobiología (INTA-CSIC), Ctra. de Ajalvir, Km. 4, Torrejón de Ardoz, 28850 Madrid, Spain.
authors: Francisco J
authors: FJ
authors: López de Saro
mesh_terms: D041801:Acidiphilium / Q000235:genetics*; D004261:DNA Replication / Q000235:genetics*; D004251:DNA Transposable Elements / Q000235:genetics*; D004269:DNA, Bacterial / Q000235:genetics*; D019143:Evolution, Molecular
chemical_list: D004251:DNA Transposable Elements; D004269:DNA, Bacterial