Examples of Gram Negative Bacteria
There are many species of Gram negative bacteria, so it is difficult to make generalizations about them. Some are commonly found strains, other are rare. Some are commensal, meaning they live on or in our bodies without causing harm. Others are pathogenic, meaning they are capable of causing disease. Some species of Gram-negative bacteria can be harmful or benign, depending on the strain. Common examples of Gram negative bacteria include:
Escherichia coli: Commonly known as simply E. coli, these bacteria are found in the intestines of humans and almost all other warm-blooded organisms. Many strains are just a normal member of the average gut bacteria. Some strains, however, like E. coli O157:H7, cause serious foodborne illness.
Campylobacter jejuni: This Gram negative bacteria is one of the leading causes of food poisoning. It is an opportunistic pathogen, meaning it usually lives in humans without causing disease but can cause illness once the individual's immune system is weakened.
Bordetella pertussis: This bacteria causes pertussis, commonly known as whooping cough. Fortunately there is a vaccine available to provide protection against this Gram negative microorganism.
Salmonella: This genus is closely related to E. coli, and it is also often found in humans without causing illness. Many strains are pathogenic, and Salmonella bacteria are responsible for thousands of cases of food poisoning each year. This bacteria can also cause typhoid fever.
Other well-known Gram negative bacteria include the causative agents of Legionnaires' disease, gonorrhea and cholera.