Uptake and processing of DNA by Acinetobacter calcoaceticus – a review

摘要: Abstract In natural transformation, DNA in the form of macromolecular fragments can be translocated across cell envelope prokaryotic microorganisms. During past two decades, several, largely mutually contradictory, hypotheses have been forwarded to explain molecular mechanism and bioenergetics this translocation process. Other biomacromolecules are bacterial as well, such polysaccharides proteins, latter for instance process assembly type-IV pili. This brings up question whether or not common components involved. Here, we review analyses Acinetobacter calcoaceticus, a Gram-negative eubacterium that is able migrate through twitching motility, also shows high frequency transformation. uptake organism an energy-dependent Upon entry into cells, integrated resident chromosome when sufficiently large region mutual homology available (200 400 bp). However, rather inefficient, on average 500 bp each incoming fragment degraded exonuclease activity. covalent attachment bulky protein molecule transforming DNA, DNA-translocation machinery becomes blocked further Since A. calcoaceticus well suited transposon mutagenesis, random mutagenesis procedure has developed, based ligation antibiotic-resistance marker chromosomal DNA. method was used generate several mutants impaired transformation Three these characterized detail. No components, macromolecules Acinetobacter, detected screen.