Binary fission theoretically results in two identical cells. However, the DNA of bacteria has a relatively high mutation rate. This rapid rate of genetic change is what makes bacteria capable of developing resistance to antibiotics and helps them exploit invasion into a wide range of environments.
Similar to more complex organisms, bacteria also have mechanisms for exchanging genetic material. Although not equivalent to sexual reproduction, the end result is that a bacterium contains a combination of traits from two different parental cells. Three different modes of exchange have thus far been identified in bacteria. (See gene transfer.)
Conjunction involves the direct joining of two bacteria, which allows their circular DNAs to undergo recombination. Bacteria can also undergo transformation by absorbing remnants of DNA from dead bacteria and integrating these fragments into their own DNA. Lastly, bacteria can exchange genetic material through a process called transduction, in which genes are transported into and out of the cell by bacterial viruses, called bacteriophages, or by plasmids, an autonomous self-replicating extrachromosomal circular DNA.
Related categories• MICROBIOLOGY
• CELL BIOLOGY
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