Tag Archives: bacteria

Bacteria in your frosted (snow) flakes!

If you’re from the Northeast or the Midwest (like I am) then you probably know that children enjoy playing in the snow. Snowball fights, snow angels, snow forts, and catching snowflakes on their tongues, children revel in the soft, downy, cold crystals. As scientists, our idea of fun has changed—following a loss of innocence, there

Quorum sensing, microbes, and squids

Bobtail SquidAll microbes communicate with members of their own species and between species. This type of communication, called quorum sensing, allows bacteria to form rich social networks with their neighbors. Bacteria use quorum sensing to keep tabs on the density of members of their species in relation to the density of other species in order to perform fantastically synchronous events that they could never accomplish working in isolation–like the successful invasion of a host. And while pathogen-host interactions are incredibly intricate, beautifully structured, and close to my heart (figuratively) I’ll be focusing on a wonderfully evolved symbiotic relationship between a microbe and a squid: Vibrio fischeri and its life partner, the Hawaiian bobtail squid.

Beware: you might turn into that pizza you’re eating

You are what you eat– it’s something health food advocates have warned us all along, but only recently have researchers completed a study that proves it. The study, published in Science Express and conducted by a team of researchers at the University of Pennsylvania led by Dr. Gary Wu of the Perelman School of Medicine, found that gut bacteria that reside on the inside and outside of the intestines grow at varying rates depending on what a person consumes. The study divided 98 volunteers into two diet groups – one rich in meat, the other rich in vegetation. Within a single day’s time, the researchers observed significant changes in the volunteers’ gut bacteria composition, proving that a person’s diet has an immediate impact on the bacteria growing in their body.

To carry out their investigation, the team monitored the diet of participants over a ten day period and checked for the presence of specific bacteria in their stool samples. They discovered that those who had a meat-rich diet had a greater amount of Bacteroide genus, while the ones who had a fiber-rich diet had more Prevotella bacteria. Human naturally have these bacteria in their gut – but only one or the other can be present. Most of the participants started out in the Bacteroides group (since the Western diet is rich in meat), transitioned to the Prevotella group when placed on the fiber-rich diet, and then switched back to Bacterioides when they returned to their usual diet.