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How Bacteria Work

Bacteria As Heroes
Sir Alexander Fleming, a bacteriologist, discovered penicillin quite by chance in 1928.
Sir Alexander Fleming, a bacteriologist, discovered penicillin quite by chance in 1928.
Peter Purdy/Hulton Archive/Getty Images

Let's take a moment to examine bacteria's good side. After all, these are the microbes that bring us tasty foods such as cheese, beer, sourdough and other fermented items. They're also the unsung heroes behind medicine and advancing human health.

We also have bacteria to thank for shaping human evolution. Science is gleaning more information from the microbiota, or the microorganisms residing in our own bodies, particularly in our digestive system and gut. Research suggests that bacteria, and the diversity and new genetic materials they bring to our bodies, have allowed humans to adapt to and exploit new food sources they previously could not use [source: Backhed et al.].

Look at it this way: Lining the surfaces of your stomach and intestine, bacteria are "working" for you. When you eat, bacteria and other microbes help you break down and draw nutrients from foods, especially carbohydrates such as corn, potatoes, bread and rice. The more diverse bacteria we consume and are exposed to contribute to this diverse community in our bodies.

Although our knowledge of our own microbial communities is nascent at best, there's evidence to suggest that a lack of certain microbes and bacteria in the body can tie into a person's health, metabolism, and susceptibility to allergens and disease. Preliminary studies in mice suggest that metabolic diseases such as obesity are linked to diversity and health of the microbiome rather than our predominant view of the "calories in, calories out" approach [source: Cox].

Also in early stages, fecal transplants involving the sharing of fecal microorganisms from a healthy individual to another person show early promise. Yeah, this might not be the best mental image, but the science and options to treat certain gastrointestinal illness looks promising. Research is being done on probiotics, microbes thought to have added health benefits, but general recommendations on their use haven't been established as of November 2014.

In addition, bacteria have been game-changers in the development of scientific thinking and human medicine. Bacteria played a lead role in the 1884 development of Koch's postulates, a series of considerations that tie a given microbe to disease.

Among other contributions, researchers studying bacteria serendipitously discovered penicillin — an antibiotic that has saved countless lives — and, more recently, an easier way to edit organisms' genomes that could revolutionize medicine [source: Marraffini]. Researchers have modified bacteria to benefit human health in many ways, including producing insulin for the treatment of diabetes.

We've only begun to understand all we can learn from our bacterial friends.