Gene Transfer via Transformation in Soil/Sediment Environments
Genes of prokaryotes can be transferred from one cell to another by three distinct parasexual processes. Two of them are accomplished by intracellular “parasites”: bacteriophages can transport genes (transduction) and plasmids can promote DNA transfer during cell contact (conjugation). The third parasexual process is genetic transformation during which free DNA is taken up by cells. This DNA uptake is controlled by bacterial genes located on the chromosome. In the past decades the physiology, biochemistry, genetics, and molecular biology of the three transfer mechanisms have been the subject of a vast number of studies. Many principles and details have been elucidated. However, as yet there is no definite answer to the question whether conjugation, transduction and transformation take place in natural bacterial habitats and, if so, what the effects are on the dynamics of natural bacterial populations.
KeywordsClay Quartz Phosphorus Mercury Recombination
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