Scientist Profile – Professor Miguel Jimenez
Miguel Jimenez, Ph.D.
Assistant Professor of Biomedical Engineering
Living cells have a prodigious capacity to continuously monitor and act upon their environment. Professor Miguel Jimenez heads el Microbial Integration Group which harnesses this capacity to augment electronic and mechanical devices with the goal of improving human health, agriculture, and the environment.
Professor Jimenez discussed some of the exciting ways he and his colleagues have already integrated living cells with man-made electronics as well as the key research challenges his team is tackling to bring such devices to fruition. He concluded with musings on woodworking, Colombian cuisine, and author Haruki Murakami.
How would you describe your research and the goals of your lab?
My lab is exploring the question: How do we integrate genetically engineered microorganisms into electronic and mechanical devices? The reason we’re excited to develop these “microbial devices” is because we believe this technology has a wide variety of applications which will include improving human health, enhancing agriculture, and protecting the environment. Living cells have an ability to sense and act upon their surroundings in very specific ways that electronic and mechanical devices can’t do effectively on their own.
What are the challenges to integrating living cells with electronic and mechanical devices?
We’re particularly interested in developing technologies that could have high impact in low-resource settings. Such settings can include the home environment, an agricultural field, and the points of care in low- and middle-income countries. Space exploration is another low-resource setting where this technology can have a big impact. In fact, we collaborated with Space Center Houston to send some stabilized microbes to the International Space Station last year, and they just recently arrived back on Earth.
Keeping in mind that guiding principle of impact in low-resource settings, we’ve defined three key challenge areas for developing this technology. One challenge concerns the growth of these cells. It’s a major strength that cells can self-replicate, but we have to figure out a way to promote robust and sustainable self-replication inside these small devices. A second challenge involves genetics. We want these genetically engineered cells to function as intended in non-laboratory environments such as soil or the human gut, so we are developing platforms to optimize genetic designs that will work robustly in these target environments.
A third challenge concerns how we transfer information between a living cell and the electronic or mechanical components of a device. One transfer medium that works well is light. For example, you might have a light-emitting diode (LED) that activates or modulates a photoactivatable protein, enabling the transfer of information into cells, and an electronic sensor that can detect the light from a bioluminescent cell, which enables information transfer out of cells. We’re trying to optimize light as a communication medium, but we’re also exploring whether there are other physical mediums we can use.
Can you describe an example of a microbial device you’ve developed?
Just before I came to Boston University, I was part of a large interdisciplinary team (which included my future BU colleague Rabia Yazicigil) that developed an ingestible microbial-electronic capsule that can be swallowed like a pill and monitors intestinal inflammation. For this system, we integrated engineered microbial cells which can sense specific biomarkers of inflammation, like nitric oxide, and generate a bioluminescent signal. The onboard electronics then convert that light signal into a wireless signal that can be read out on a personal device or an external receiver.
Development of the capsule involved wrestling with challenges like keeping the cells wet and the electronics dry while still enabling information transfer between the two. We also developed a way of stabilizing the microbial cells as dry powders, in a way that doesn’t require any refrigeration, and showed that we can extend their lifetime beyond six months. These stabilized microbes, which we call “synthetic extremophiles,” open a new way of manufacturing with living systems that wasn’t possible before (these are the same kind of stabilized microbes that we sent to the International Space Station).
How did your journey as a scientist lead you to the development of microbial devices?
Both of my parents are electrical engineers, and so as a child I wanted to be an engineer as well. In high school I started reading science fiction that featured nanotechnology, and I imagined how cool it would be to make microscopic robots. Later in high school I was amazed by this video (produced by the Walter and Eliza Hall Institute of Medical Research) which showed how DNA polymerase catalyzes the replication of DNA, and I realized that the tiny robots I’d been dreaming about were not going to be made of tiny metal screws and bolts but would actually be made out of the proteins and molecules that exist inside cells.
As an undergraduate I fell in love with organic chemistry, which to me felt like learning a new language, and I was lucky enough to work in a research lab that connected organic chemistry to real world applications—we were making molecular libraries to develop therapies. In my PhD work I was part of group that looked at cells as a sort of chemistry flask, and this is where I learned the tools of genetic engineering. I worked on a project funded by the Bill & Melinda Gates Foundation to develop low-cost diagnostics, and our solution was to genetically encode all the different functions of a traditional diagnostic device into the genome of baker’s yeast. Eventually, while working as a research scientist at a mechanical engineering department, I started to explore how we might integrate cells into electronic and mechanical devices.
Do you have hobbies outside the lab?
I’m a very visual person, and as an undergraduate I took several studio art courses ranging from painting to sculpture and woodworking. It became harder to flex those artistic muscles with the increasing demands of being a full-grown adult, but I continue to be very excited about woodworking, and recently I’ve been directing that energy toward functional projects for my family, like a breakfast nook and table that I made from scratch.
What is your favorite food?
I was born in Bogota, Colombia and came to U.S. when I was eight years old. I still love ajiaco, which is a Colombian potato stew that is prepared and served in a way that’s very communal (the high altitude of the Bogota region is great for growing potatoes). We make ajiaco for the holidays or important events, serving this base potato soup with many different dressings so that each person can fix the ratios to their liking, and I just enjoy that family and community process of eating that specific dish.
And your favorite book?
I enjoy science fiction and dystopian stories. I also seek novelty—I love being surprised—so I was really blown away by Haruki Murakami’s 1Q84. It’s quite long, but it’s one of those books that transports you to a world that is both imaginative and very realistic.
*This interview was conducted and edited by Jim Cooney.