image: Marcos de Moraes, center, with his lab team at Rice University.
Credit: Rice University.
When bacteria battle for survival, they do so with microscopic precision. Some produce toxins that target rival microbes, shaping not only their own fitness but the structure of entire microbial communities. Marcos de Moraes, assistant professor of biosciences at Rice University, is fascinated by these microbial skirmishes and how they might be harnessed for biotechnology.
Now, with support from the National Science Foundation (NSF) Faculty Early Career Development Program (CAREER), de Moraes will study a little-understood family of bacterial toxins known as deaminases. The five-year, $1.2 million grant will fund research into the molecular mechanisms and evolutionary roles of these toxins as well as a robust educational outreach effort aimed at making biosciences open to all, including differently abled persons with mobility impairments and other physical or sensory challenges.
“We know these toxins can be potent and useful, but we don’t know what most of them are doing in bacterial cells,” de Moraes said. “My goal is to understand how these toxins function at a molecular level, how they shape bacterial communities and how we might turn them into tools for genome engineering or biotechnology.”
Deaminase toxins, formally named bacterial deaminase toxin families, can alter genetic material by chemically modifying nucleotides. Some are already being used in genome editing tools, but many others are not well understood. De Moraes’s lab will use a combination of structural biology, computational modeling and biochemical analysis to investigate how these toxins work and why bacteria deploy them.
One of the project’s most novel aspects is the creation of a Deaminase Activity Report Tool (DART), which will directly measure the impact of these toxins on other cells in complex microbial environments like soil or the human gut.
“Most studies look at changes in community composition and try to infer what happened,” de Moraes said. “With DART, we’ll be able to pinpoint which bacteria were targeted and how, giving us a much clearer picture of interbacterial interactions in real time.”
Another aspect of the project is to understand what happens to cells that survive exposure to the toxins.
“What doesn’t kill you mutates you,” de Moraes said. “We know that bacteria’s DNA can be modified by the toxin, but how that affects their physiology is unknown. It could play a major role in processes such as antibiotic resistance or pathogenesis.”
The CAREER Award is not only a recognition of de Moraes’s innovative science, but it also supports his plans to broaden participation in research, especially for persons with disabilities. NSF studies have shown that while about 26% of Americans identify as having a disability, only about 7% of doctorate recipients in the biological sciences fall into that category.
“This disparity shows how many students are being left out of the research enterprise,” de Moraes said. “Many times, they simply do not have the necessary conditions to work because lab spaces rarely are ADA-compliant. We want to change that by creating a lab environment that doesn’t select against a group of people.”
His educational plan includes offering paid, hands-on research experiences to students from both Rice and Houston Community College. Research opportunities will be offered to students regardless of their background, and resources will be available to students who are differently abled. The lab will follow principles of universal design, featuring adjustable benches, electronic pipettes and other adaptive equipment to accommodate different needs.
De Moraes is also collaborating with Maria Oden, director of Rice’s Oshman Engineering Design Kitchen, to co-develop new assistive lab tools tailored for students with mobility challenges.
By combining cutting-edge research with a commitment to removing barriers in education, de Moraes’s project exemplifies the dual mission of the NSF CAREER program: scientific innovation and societal impact.
“Our understanding of bacterial toxins has the potential to transform how we approach biotechnology, health and agriculture,” de Moraes said. “At the same time, we open our scientific community to all talents, making it stronger and more creative. That’s what this award makes possible, and I’m incredibly honored to receive it.”