Genetic Cross-Talk

Bacteria can do tricks that your dog cannot do. A bacterium can acquire DNA from another completely unrelated species of bacteria just by living in the same area. For example, if you take cyanobacteria, a type of bacteria that normally live in the oceans and carry out photosynthesis, and mix them in a test tube with a population of E. coli, the bacteria that normally live in your large intestines, something odd can happen. If you let them sit together overnight, some of the E coli cells will link up with the cyanobacteria using a microscopic hose and then transfer some of their DNA into the cyanobacteria [1]. Once the E. coli DNA is inside the cyanobacterium, the cellular machinery will then splice the E. coli DNA into the chromosome. This would be like your dog somehow acquiring cat DNA and the ability to purr simply by sleeping on the same bed with the cat!This process of acquiring foreign DNA is known as lateral gene transfer (LGT) or horizontal gene transfer(HGT). A large number of scientists consider LGT to be a powerful force in bacterial evolution.