DNA transfer Prokaryote

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3d animation of prokaryotic cell shows elements compose it


natural bacterial transformation involves transfer of dna 1 bacterium through intervening medium. unlike transduction , conjugation, transformation bacterial adaptation dna transfer, because depends on numerous bacterial gene products interact perform complex process. bacterium bind, take , recombine donor dna own chromosome, must first enter special physiological state called competence. 40 genes required in bacillus subtilis development of competence. length of dna transferred during b. subtilis transformation can as third whole chromosome. transformation common mode of dna transfer, , 67 prokaryotic species far known naturally competent transformation.


among archaea, halobacterium volcanii forms cytoplasmic bridges between cells appear used transfer of dna 1 cell another. archaeon, sulfolobus solfataricus, transfers dna between cells direct contact. frols et al. found exposure of s. solfataricus dna damaging agents induces cellular aggregation, , suggested cellular aggregation may enhance dna transfer among cells provide increased repair of damaged dna via homologous recombination.








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