Escherichia coli is the usual laboratory model for studying bacterial genetics and molecular biology.
E. coli is a rod-shaped bacterium commonly found in the intestines of humans and other warm-blooded animals. Most strains are harmless, and its relatively simple biology, rapid growth, and well-understood genetics made it exceptionally useful in research.
Scientists have used E. coli to investigate DNA replication, gene regulation, mutation, recombinant DNA, and protein production. The famous K-12 laboratory lineage is distinct from disease-causing strains such as enterohemorrhagic E. coli O157:H7, which can cause severe foodborne illness.
A common mistake is treating “E. coli” as synonymous with food poisoning. The species contains many strains with different traits. Some laboratory strains are also engineered to manufacture medicines and research proteins, including forms of human insulin.