Mastering Microbes for Army Solutions
The synthetic biology-related work that scientists at the Army Research Laboratory are performing may seem as if it is taken from a science fiction novel: harnessing the DNA of microbes to engineer military solutions such as self-healing paint on a tank. But to support soldiers of the future, this may be what is needed, a researcher says. The Army has to prepare soldiers to fight in multidomain operations across dense urban environments, megacities or austere environments, and synthetic biology capabilities could provide fuel sources, protective coatings, food or other necessities.
“All biology is capable of replicating and healing itself,” explains Bryn Adams, research biologist in the Army Research Laboratory’s (ARL’s) Biotechnology Branch, a part of the Army Futures Command and the Combat Capabilities Development Command. “If you look at the diversity across the living kingdom, you have everything from small single-cell organisms that can sense tiny particles in their environment and alter their behavior in response to that in fractions of a second, all the way up to things like trees. So you’ve got this incredible complexity and diversity, and it’s all encoded by the same principal building blocks of DNA. So if we can understand, at the DNA level, how that translates to this huge diversity of properties, we can go after properties that are already naturally occurring, in order to harness their capabilities to do things for soldiers.”
Adams, a scientist at ARL for eight years, received her doctorate degree in interdisciplinary biology from the University of North Carolina (UNC) at Charlotte. She is appreciative of that interdisciplinary experience, working with other UNC scientists across chemistry, physics and engineering, which has helped her collaborate with other ARL scientists across various programs to find unique solutions for the Army. Currently, Adams is leading a team of scientists researching military-related synthetic biology applications including: (1) precision material synthesis, (2) agile expedient manufacturing, (3) living materials, (4) human performance, and (5) autonomous sensing.
A core part of those efforts stems from the ability of the scientists to engineer microbes from organisms by altering their DNA, she says.
To extract the DNA out of the cells of microbes and put different pieces of DNA together, the researchers are starting to involve robotics and machine learning algorithms in their lab work, which speeds up workflow, lowers costs and reduces error. The robotic systems are able to interrogate hundreds of thousands if not millions of samples, allowing the scientists to try different combinations and permutations, Adams says.
“Instead of having to extract DNA by hand with a single person, the rate at which we’re able to accelerate this technology is really taking off,” she notes. “The robots give us the precision that we need, and they can run samples over and over again. The low cost at which we can do this and the speed at which it can be done now really opens up all kinds of possibilities.”
For the researchers to engineer microbes for military purposes, however, they cannot just use any old microbes, Adams states. They are working with nontraditional or undomesticated microbes, which means they are not relying on common laboratory organisms, such as E. coli, which are easier to work with, but are not helpful for researchers looking for synthetic biology applications for soldiers in austere environments.
“The big focus for me is moving genetic engineering outside of using laboratory organisms,” she explains. “Domesticated microbes, things like E. coli, are easy to grow. Researchers have been studying its genes and its metabolism since probably the 1800s. But the downside of that is it just is not capable of surviving outside the lab. … It’s such a spoiled little dog that wears cute outfits and sits in a handbag. And that’s never going to work for us in the military. So we need to move to more robust, undomesticated bacteria.”
To acquire undomesticated microbes or bacteria, Adams relies on her experience in applied environmental microbiology in which she has “isolated organisms from marine environments, soil, landfills, all kinds of oysters and all kinds of weird things.” The ARL team she is leading is learning how to isolate organisms from things the military would have interest in turning into a biomaterial, such as pulling microbes from the sides of a tank or off a piece of a drone. The scientists then study how to grow the undomesticated microorganisms in the lab to begin genetically modifying them, she says.
“It is getting them back in the lab and understanding how to grow them and start understanding how to manipulate them so that we can then potentially integrate them into an environment, such as a specialty paint on a tank that has a sensing capability or a self-healing capability,” Adams offers. “Or for a drone that’s going to be doing reconnaissance in a very dry, hot environment. You would want an organism that is perfectly happy living in a hot, dry environment to be the bio of your biohybrid coating on that drone.”
As part of precision material synthesis research, ARL scientists are examining how bacteria create cellulose, Adams continues. “One of the things some bacteria make really well is cellulose, so you can have them make differently modified cellulose that is all programmed in their DNA synthetically here in the lab,” she states. “They’re able to make complex structures out of the cellulose, which can be anything from a specialty coating to some sort of a wearable material. If we can understand how that happens and tap into that, we can make some very complex structures that traditional chemistries just can’t do.”
Another synthetic biology capability, agile expedient manufacturing, will offer flexibility to tomorrow’s small expeditionary forces, who will have to carry everything they need. When future soldiers do not have what they require, they can rely on the indigenous materials of their environment along with synthetic biology, Adams clarifies.
“Soldiers are going to need to be able to utilize what’s around them: grass, soil and water, the natural flora and fauna of their environment to be able to make the things they need such as fuel, food, energy and materials,” she stresses. “For example, if they have a powdered mix of bacteria that they just have to add water and maybe grass to, set it in the sun, and a couple of hours later they’ve got fuel, or they’ve got the plastic precursors to be able to 3D-print a part or a tool.”
ARL scientists also are examining how to harness living materials or put biological organisms into substances. This could be applied, for example, to defective body armor. The added biohybrid material could heal itself, through genetic modifications, she suggests.
Additionally, the ARL’s research includes examination of how to apply synthetic biology to improve human performance, Adams mentions. “Another area that we’re kind of exploring involves microbiomes,” she says. “We know how important the gut microbiome is, as well as our skin microbiome. The organisms that live on our skin help protect us from getting infections when you get cut because they act like a barrier, and the same thing happens in our gut. Being able to understand the human microbiomes and then being able to utilize those community members to work better, then we will have healthier soldiers that perform better.”
In addition, harnessing the autonomous sensing properties of microbes’ natural sensors remains promising, Adams states. “With microbes, they are so small and they have to be so in tune with their environment because a very small change in their environment can really impact whether they live or die,” the scientist clarifies. “So they’re really good at sensing very small changes. It’s not just sensing molecules, it’s changes in pH, changes in oxygen, or changes in concentrations of sugars and salts.”
As part of this effort, researchers are looking to photosynthetic organisms, such as cyanobacteria, which use the sun for energy. “So you don’t have to feed them sugars or anything else,” Adams states. “And now you have self-powered components that are living. If we can tap into that, we have these self-sustaining sensors that can help us monitor what’s going on around the soldier. And because we’re getting really good at reprogramming DNA, we can reprogram them to start monitoring [whether] the soldier is getting fatigued or stressed, [or if they] are having issues due to lack of sleep or maybe an onset of an infection that they’re not aware of yet. All that sort of stuff can be sensed with microbes.”
Those synthetic biological sensors can be integrated into wearable technologies, the scientist mentions, like a personal fitness device. “It could be a patch that they just stick on their arm or some place on their body, and it’s able to monitor the biomarkers that are coming off of their skin to get to a [reading] of them.”
Other scientists in the ARL’s biotechnology branch are working on developing the specific sensor parts that would go into such wearable technologies, while another group is looking into how to interface the organisms with the electronics of the wearables, Adams shares.
“Since the organism is able to communicate to some sort of microprocessor or chip, you can then expand it to monitoring a whole group of soldiers, and that information can be sent via Bluetooth or something like that to a squadron leader,” she emphasizes. “Then not only do they know how one specific individual is doing, but they also have a real-time snapshot of the whole group.”
Being in the sensors and electronics directorate, this is an important capability, Adams says. “The possibilities of where this can go are really almost endless, especially when you start interfacing all these different components together. You can build some really unique biohybrid materials.”
Synthetic biology will continue to be a major priority for the Army, as well as the Defense Department, Adams stresses, although she acknowledges that it is a long-term effort.
“The Office of the Secretary of Defense has identified synthetic biology as one of the top priority areas up there with artificial intelligence, so we have a lot of high level support,” she says. “And we’re starting to show them what is possible. It is very exciting and sometimes also a little scary, especially when I start talking about how I can come up with DNA sequences that encode things that have never existed in nature. But this is definitely for 2040 and beyond.”
