top of page

The Bacteria Cookbook

"The Bacteria Cookbook" artwork. Cartoon bacteria in a bowl with a whisk.


NGSS Standards:


Bacteria are among the simplest forms of life on Earth. One cell is identical to the next, sharing the same DNA. So why do they all act so differently? Turns out, there’s a “cookbook” inside each teeny tiny bacteria cell, and every single bacteria has different ideas about the recipes it wants to make. Mary Dunlop is a biological engineer who’s a creative cook both in the kitchen and the lab - and she’s cooking up her own experiment of science discovery.


Photo of Mary Dunlop

Mary Dunlop is a biological engineer, or synthetic biologist. Synthetic biology is about using biological parts already found in nature to make new things, like medicine, food, or fuel. But before engineered cells can become the factories of the future, scientists like Mary have to learn the basic science behind the cell.

Learn more about Mary's work on her lab's website! (It's pretty sciencey.)

In the episode, we talk about Mary's cell "movies." Watch one for yourself, below!

Here's Mary's description of what you're seeing in those little green lines:

In this movie, bacteria that contain a green fluorescent protein reporter are grown in many small, parallel chambers. Cells are trapped at the top of the chamber and as they grow and divide, they are pushed down and eventually out the bottom of the chamber.

In this experiment, the scientists shine light on the right half of the image starting at 3 hours, switch to the left half at 6 hours, and alternate after this. Each single cell is about 2 microns long and the movie shows 18 hours of data.

Wow, can you believe that clip is a time lapse of 18 hours!? Imagine how slowly the cells are growing. Mary says they divide every half hour or so.

These cells are also super tiny! A micron is a micrometer, or one millionth of a meter. One micron is not visible to the human eye - you'd need 50 microns to get up to the width of a human hair.

Look closely, and see if you can see the changes between the scientists flashing the lights from the left to the right. How do the cells respond?

Mary and her team are trying to recognize patterns in these movies that could predict whether individual cells are weak or strong. Now that you've seen the movie, can you imagine how they might do that, comparing many movies to each other?


Synthetic biology is one of the newest kinds of biology. It combines a lot of different types of research. For scientists like Mary, it's like engineering on a very small scale, with parts that are constantly changing.

Want to learn more about synthetic biology? Watch this short film!

If you'd like to explore synthetic biology for yourself, in the classroom and outside, there's a wonderful organization called Biobuilder.

This episode was supported by the National Science Foundation under award number MCB 2032357.


bottom of page