Battling bugs by shutting down supply lines
To bacteria, life is one big banquet. Most of their attention—if they have what you can call attention—goes to finding and obtaining food. And while we may see the disease—causing members of their ranks as our enemies, the bugs don't set out to make us sick, says Maris Fonseca. They’re just trying to get a good meal, and to them, we’re nothing more than a buffet table.
“All they want to do is satisfy their dietary needs, and it is from us that they obtain their nutrients,” says Fonseca. Working in Michele Swanson’s laboratory, Fonseca is investigating what cellular components the bacterium Legionella pneumophila, which causes Legionnaires’ Disease, uses to acquire nutrients from its host.
“Understanding how Legionella feeds itself can help us identify agents that can inhibit its growth,” Fonseca says. Such findings may apply to other organisms with similar lifestyles, such as Chlamydia, which causes a common sexually transmitted disease and is more difficult to study in the lab than Legionella.
Fonseca’s choice of research subjects allows her to combine a fascination with basic scientific puzzles with a desire to improve human health – an aspiration that arose in her teens, when cancer touched her own family. She chose U-M’s Microbiology and Immunology Department for her postdoctoral training because of its active research programs in her specific area of interest.
“I was really attracted to the fact several laboratories in this department are investigating how bacteria like Legionella or Listeria or E. coli obtain nutrients and how the strategies they use in feeding themselves are related to the mechanisms they use to cause disease,” she says. In addition, she appreciated the opportunity to interact with renowned microbial physiologist and former department chair Frederick Neidhardt.
For Fonseca, such links between generations of scientists are both inspiring and essential to ongoing research.
“The amount of information that we're able to gather in this post-genomic era has exploded quite impressively. But even though we may have more information coming at us today than ten years ago, we still use tools developed by scientists who came before us, integrating them with new tools designed for handling large amounts of data.”
New tools and technologies also open up opportunities for sparking interest in students who may be tomorrow’s scientists, and the more Fonseca delves into the intricacies of Legionella’s dining habits, the more she looks forward to a career that will combine research with teaching undergraduates.
“It’s exciting to be part of this generation of scientists and to have the opportunity to inspire the next generation, especially at this point in time, when the genomes of so many bacteria and other organisms have been sequenced and are being sequenced by the minute,” she says. “We have a unique opportunity to combine what the computer tells us from all those sequences with what we learn in the lab about how bacteria acquire and metabolize nutrients, and with this knowledge in hand and using bacteria as models, we're better prepared than ever to teach students about what's known and to motivate them to explore yet-unanswered questions of biology.”
