the secret life of sugar
Happy new year from Bite-Sized Biology! I hope you all had a wonderful holiday season. One of my favorite ways to celebrate the holidays is to bake lots of holiday cookies, and this year I made a big batch of molasses spice cookies for my lab’s holiday cookie exchange. They were so tasty that they disappeared before I could even take a picture! In return, I received every kind of cookie from cherry chocolate-chunk to chocolate-hazelnut pinwheels.
Of course, baking lots of holiday cookies also means eating lots of holiday cookies. And that means eating lots of sugar. But did you know that sugar is more than just a tasty treat the bane of a holiday dieter’s existence? Sugar plays several important roles in our cells and is even a part of our DNA! What we call “sugar” is really just a few molecules — namely sucrose, glucose, and fructose — that belong to a much broader class of sugar molecules called carbohydrates. The sugar “ribose” is an important building block of our DNA. Ribose is a five-carbon sugar that resembles fructose, the sugar found in fruit.
Sugars can also act as informational molecules in the cell. Different combinations of sugars like mannose, galactose, and fucose can decorate the surfaces of proteins and lipids to create a special cellular code: the sugar code. This sugar code is particularly important for helping cells recognize and interact with one another. Sugars displayed on the outer surfaces of cells can mediate cellular interactions and provide important identification signals. For example, our T cells (a type of white blood cell) take advantage of the sugar code to target sites of inflammation. Several viruses and bacterial toxins use the sugar code to infect cells by binding to specific groups of sugars on the cell surface. Sugar-based pharmaceuticals like heparin (an anticoagulant) and acarbose (an anti-diabetic drug) are even commonly used to treat a variety of ailments. So think about that the next time you whip up a batch of delicous, sugary cookies!