Most bacteria live freely in the environment — in soil and water, in the air, and in and on the human body. Some, though, live a little less freely: they depend entirely on other bacteria, latching onto them and leeching out the critical nutrients they need for survival.
While these parasitic bacteria — called Saccharibacteria — have historically ranked among microbiology’s most understudied organisms, they are now at the centre of the research that McMaster University graduate student Jake Colautti is conducting during a yearlong exchange at Yale University.
“For a long time, these bacteria could not be well studied in a lab due in large part to their dependence on other bacteria for critical resources,” Colautti explains. “But that changed recently when Joseph Mougous and his team at Yale developed new tools to genetically manipulate them.”
In the Mougous Lab, based at Yale’s Microbial Sciences Institute, Colautti is leveraging these new tools to answer ambitious, fundamental questions about the biology of these bugs.
Colautti says early studies show that these bacteria are fixtures in the oral microbiome — the dense ecosystem of microbes that live in the human mouth — and may contribute in some way to the prevention of inflammatory gum diseases. He also believes that Saccharibacteria could have additional health implications, but says that we can’t begin to understand any of them until we first understand their basic biology.
“Asking and attempting to answer big-picture, ambitious, and unbiased questions about these bacteria can teach us a lot not only about their lifecycle, but also about bacterial interactions more broadly,” he says.
Training in the Mougous Lab is something of a legacy moment for Colautti, who is typically based in the laboratory of John Whitney, an associate professor at McMaster and a member of the Michael G. DeGroote Institute for Infectious Disease Research. Whitney himself completed a postdoctoral fellowship under the supervision of Mougous a decade prior, when Mougous was based at the University of Washington, and can say from experience that the opportunity offers Colautti a chance to “train under an internationally renowned scientist and in one of the world’s leading labs for studying bacterial competition and interaction.”
Mougous is not only a leading expert, but one of the most distinguished researchers in his field, Whitney says. This is reflected in his election to both the National Academy of Sciences and the Howard Hughes Medical Institute — among the highest honours US-based scientists can receive.
Working with Mougous has been made possible by Colautti’s receipt of the Michael Smith Foreign Study Supplement, one of the most competitive and prestigious Canadian travel awards provisioned by the federal government. The grant, worth $6,000, supports high-calibre Canadian graduate students in building global linkages through research placements at foreign institutions.
For Colautti, the opportunity to train in the US has been foreign in more ways than one. While he did move away from home to train at McMaster, he says this is his first true study-abroad experience.
Back at McMaster, campus is only an hour away from his hometown of King City, Ontario — based just north of Toronto. Now nine hours and a border away in New Haven, Connecticut, Colautti admits that he’s plunged well outside of his comfort zone, but says the experience has been fulfilling so far.
“It was all kind of intimidating at first,” he says. “In an instant, your entire social circle disappears and is just as suddenly replaced by an entirely new cast of people. But everyone has been great. They all really love science — and so do I — so it’s been easy to bond with the team in the Mougous Lab.”
That bonding, he says, was accelerated by the Winter Olympics. Being the only Canadian on the team, Colautti was dubbed the group’s de facto hockey person during the Games, despite being a casual observer of the sport at best. He says watching Canada’s Olympic hockey teams lose back-to-back gold-medal games to America, in America, with American colleagues was an unusual but memorable experience.
Away from the lab, Colautti is trying to immerse himself in the Yale culture as much as he can. He lives with a neuroscience postdoc and a geochemistry grad student in a small campus community called East Rock, which is walking distance to the Ivy League school’s main campus. He likes to frequent the university’s art gallery, which displays original Monets, van Goghs, and Picassos, and says that the school’s strength in the liberal arts is palpable around town.
“The opportunity to learn beyond just science has been enriching,” he says. “Just being at my house, around the neighbourhood, you really feel like you’re part of a world-class humanities institution.”
But while the cultural ambiance has been a highlight of his sabbatical, Colautti says it’s all merely a cool backdrop to the work he’s there to do. He’s intent on cramming as much science into the year as possible, as for the first time in a long time, he’s able to devote his whole self to the lab.
As a trainee in McMaster’s MD/PhD Program, Colautti typically oscillates between two very different worlds — the bench and the clinic. And while he loves keeping both sides of his brain fresh, he says he’s relishing this rare stretch of uninterrupted scientific exploration.
His plan is to master the Mougous Lab’s tools and techniques as well as he can, so that he can bring that experience back home and leverage it for new and continued research in the Whitney Lab at McMaster.
“I’m here this year learning how to do this very specialized research, and then I’m going to come back to Canada and be the only microbiologist in the country that knows how to do this kind of stuff,” he says. “It’s a great opportunity for me.”