Microbiome Monday: Halloween Candy and Your Microbiome

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It's Microbiome Monday again! Before the Museum’s upcoming exhibition The Secret World Inside You opens November 7, we’re offering weekly primers on the microbiome and the research surrounding it from Curators Rob DeSalle and Susan Perkins, as well as from other scientists who are working in this exciting field.

In the days following Halloween, plenty of kids—and some of their parents—are working their way through a haul of Halloween candy. Some bacteria will transform that sugar into plaque. But did you know there are other microbes working to keep these cavity causers at bay? On this Microbiome Monday, meet some of the microbes in your mouth!

Halloween Candy

Sugary candy can feed the microbes in your mouth that cause cavities.

Courtesy of Luke Jones on flickr


Who isn’t familiar with the dreaded strep throat? An extremely painful form of pharyngitis, or inflammation of the back of the throat, it’s caused by the bacterium Streptococcus pyogenes—hence its name—which is also the culprit in rheumatic heart disease. But there are more than 50 recognized species of Streptococcus, many of them regular denizens of the human mouth, respiratory tract, and elsewhere.

Streptococcus

Artists rendering of a Streoptococcus bacterium.

© AMNH/B. Peterson


Some, like S. pyogenes, are proven pathogens, the cause of everything from cavities (S. mutans) to pneumonia (S. pneumonia). But others seem to do no harm, and may even help by working against troublesome strains of fellow streptococci. Streptococcus salivarius, for example, which is found in the human mouth and respiratory tract, can be dangerous, even lethal, to people with weakened immune systems in the rare event it escapes outside the oral cavity. But in the mouth, it appears to help prevent both gum disease and tooth decay. When cultured side by side in the lab, S. salivarius inhibited the formation of decay-causing plaque by S. mutans.