Blar i forfatter "Johnsen, Pål Jarle"

Viser treff 21-26 av 26

    • Steady at the wheel: Conservative sex and the benefits of bacterial transformation 

      Ambur, Ole Herman; Engelstädter, Jan; Johnsen, Pål Jarle; Miller, Eric L.; Rozen, Daniel E. (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-09-12)
      Many bacteria are highly sexual, but the reasons for their promiscuity remain obscure. Did bacterial sex evolve to maximize diversity and facilitate adaptation in a changing world, or does it instead help to retain the bacterial functions that work right now? In other words, is bacterial sex innovative or conservative? Our aim in this review is to integrate experimental, bioinformatic and ...

    • Strong pathogen competition in neonatal gut colonisation 

      Mäklin, Tommi; Thorpe, Harry Arthur Frank Wright; Pöntinen, Anna Kaarina; Gladstone, Rebecca Ashley; Shao, Yan; Pesonen, Maiju; McNally, Alan; Johnsen, Pål Jarle; Samuelsen, Ørjan; Lawley, Trevor D.; Honkela, Antti; Corander, Jukka (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-01)
      Opportunistic bacterial pathogen species and their strains that colonise the human gut are generally understood to compete against both each other and the commensal species colonising this ecosystem. Currently we are lacking a population-wide quantification of strain-level colonisation dynamics and the relationship of colonisation potential to prevalence in disease, and how ecological factors ...

    • Substitutions of short heterologous DNA segments of intragenomic or extragenomic origins produce clustered genomic polymorphisms 

      Harms, Klaus; Lunnan, Asbjørn; Hulter, Nils; Mourier, Tobias; Vinner, Lasse; Andam, Cheryl P; Marttinen, Pekka; Fridholm, Helena; Hansen, Anders Johannes; Hanage, William P; Nielsen, Kaare Magne; Willerslev, Eske; Johnsen, Pål Jarle (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-12-27)
      In a screen for unexplained mutation events we identified a previously unrecognized mechanism generating clustered DNA polymorphisms such as microindels and cumulative SNPs. The mechanism, short-patch double illegitimate recombination (SPDIR), facilitates short single-stranded DNA molecules to invade and replace genomic DNA through two joint illegitimate recombination events. SPDIR is controlled by ...

    • Testing for the fitness benefits of natural transformation during community-embedded evolution 

      Winter, Macaulay; Harms, Klaus; Johnsen, Pål Jarle; Buckling, Angus; Vos, Michiel (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-08-01)
      Natural transformation is a process where bacteria actively take up DNA from the environment and recombine it into their genome or reconvert it into extra-chromosomal genetic elements. The evolutionary benefits of transformation are still under debate. One main explanation is that foreign allele and gene uptake facilitates natural selection by increasing genetic variation, analogous to meiotic ...

    • Tn1 transposition in the course of natural transformation enables horizontal antibiotic resistance spread in Acinetobacter baylyi 

      Kloos, Julia Maria; Johnsen, Pål Jarle; Harms, Klaus (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-03)
      Transposons are genetic elements that change their intracellular genomic position by transposition and are spread horizontally between bacteria when located on plasmids. It was recently discovered that transposition from fully heterologous DNA also occurs in the course of natural transformation. Here, we characterize the molecular details and constraints of this process using the replicative transposon ...

    • A Trade-off between the Fitness Cost of Functional Integrases and Long-term stability of Integrons 

      Starikova, Irina; Harms, Klaus; Haugen, Pål; Lunde, Tracy Munthali; Primicerio, Raul; Samuelsen, Ørjan; Nielsen, Kaare Magne; Johnsen, Pål Jarle (Journal article; Tidsskriftartikkel; Peer reviewed, 2012)
      Horizontal gene transfer (HGT) plays a major role in bacterial microevolution as evident from the rapid emergence and spread of antimicrobial drug resistance. Few studies have however addressed the population dynamics of newly imported genetic elements after HGT. Here, we show that newly acquired class-1 integrons from Salmonella enterica serovar Typhimurium and Acinetobacter baumannii, free of ...