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In microbial communities, cell lysis releases DNA into the surroundings.
When a cell takes up this free DNA and stably integrates it into its genome, the process is called transformation.
A cell that can effectively take up foreign DNA is called competent.
Some bacteria and archaea show natural competence, gaining nutrients like carbon, nitrogen, and phosphorus from the free DNA.
Many proteins regulate competence. Autolysins make the cell wall permeable. Membrane-associated DNA-binding proteins transport DNA into the cell.
Nucleases degrade one strand of the incoming DNA, while competence-specific proteins protect the other until homologous recombination integrates it.
RecA-mediated recombination facilitates strand exchange, incorporating the foreign DNA into the host genome.
The recombinant cell passes on the integrated DNA to its progeny, resulting in a genetically altered lineage.
Transformation can be induced in various cells, including yeast and plants, through electroporation. High-voltage pulses create charge separation across the membrane, forming transient pores that increase permeability and allow DNA to enter.
Microbial communities are dynamic environments where cell lysis releases free DNA into the surroundings. Other cells can take up this extracellular DN…
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