Genetic engineering (also called genetic modification) is a process that uses laboratory-based technologies to alter the DNA makeup of an organism. The advantages of using bacteria for biotechnology and genetic engineering include their simple non-compartmented structure, the accessibility of their genetic material, and the fact that bacteria are among the fastest reproducing organisms in the world, doubling every 4 to 20 minutes. For example, the bacterium Escherichia coli can divide every 20 min in the laboratory under aerobic, nutrient-rich conditions.