There are tiny bacterial cells exploding all around us.
Only we can’t see them.
It’s like an invisible battlefield – a super microscopic world where bacteria are infected by even tinier viruses called phages. They get inside, feed and multiply until the bacterial cell – well, yes – explodes. Only, in science, it’s called lysing.
In a world where antibiotics are becoming less effective, science has turned to the relatively-unknown phage for answers. There are many different kinds – a very abundant but understudied culture because most have yet to be discovered.
Three Georgia College biology students are participating in an international research project based at the University of Pittsburgh. Each has uncovered new bacteriophages unknown to science – until now.
And they got to name them.
- “Waits” is a 20-sided phage with a tail, discovered by biology graduate student Audrey Waits of Charlotte, North Carolina. The harmless bacteria it feeds upon is found in small quantities on human skin. But, in rare cases, the bacterium creates an outer-layer “biofilm” that sticks to long-term catheter tubes. This can cause infection in patients with weak immune systems. Waits’ phage is a natural predator of this bacteria – making her research valuable.
- “Adonis” - meaning “handsome, strong man” in Greek - is a fairly large phage discovered in some “really nasty soil” by junior biology major Shea Morris of Byron. It destroys a harmless but potentially-important bacteria within the family of infectious microbes that causes tuberculosis. Morris hopes her phage may someday help scientists develop a cure.
- “SheaKeira” was discovered by sophomore biology pre-med major Keira Stacks of Peachtree City, who was working with Morris when she took bacterial soil samples at Lake Laurel in Milledgeville. Stacks is just beginning to characterize her phage and hopes the hexagon-headed, long-tailed virus will also hold implications for science.
“The isolation, sequencing and analysis of these novel bacteriophages by our students will add to our body of knowledge of this genetically-diverse population. Relatively little is known about the evolution of bacteriophages,” said Dr. Indiren Pillay, chair of biological and environmental sciences.
College and high school students worldwide are participating in the project. They enter discoveries into the Actinobacteriophage Database, which collects information for the Pittsburgh Bacteriophage Institute at the University of Pittsburgh’s department of biological sciences.
The project’s goal is to encourage scientific research in youth. But it also promotes the DNA sequencing and characterization of useful viruses.
In France and Eastern Europe, phage is used to treat infection through shots, pills or phage-saturated bandages. In the U.S., antibiotics are more-widely used. But phage could be the next frontier, as bacteria become more resistant to medicine.
New phages are easy to find, but little has been done in the Southeast. So the odds of finding them here are good. An online map shows a concentration of phage found around Atlanta. But new bacteriophage discoveries at Georgia College are alone in central and southeastern portions of the state.
“We’re lucky to be in a geographical region, where not a lot of sampling has been done,” Waits said. “For all we know, the phages we’re looking at have been around hundreds of thousands of years. We just hadn’t found them yet.”
Morris found Adonis down a deep ravine in “a really obscure place” at Lake Laurel. Waits found hers in less-traveled soil at the Oconee River at the Greenway in Milledgeville.
Students looked for evidence of lysing - bacteria bursting apart due to multiplying phage. They added nutrients to make bacteria grow, which also created a good environment for phage to reproduce. They isolated the phage by straining it, like coffee, through a filter.
Through DNA sequencing, students could determine if their phage looked different in size and shape from known varieties.
Then Morris and Waits took their projects a step further.
Morris is studying the effect weather has on multiplication of bacteriophage. She believes phage should be collected in warmer weather. If her hypothesis is correct – it might answer why the South is an ideal place to discover new varieties.
The bacteria Morris found is related to one that causes tuberculosis, which infects a third of the world’s population and kills roughly 3 million people a year.
“I hope my phage will someday be used to attack the infectious bacteria that causes TB,” she said. “That’s what’s really cool about phage. They specifically attack that one bacteria. They have no desire to attack anything else.”
Waits’ study relates to the biofilm surrounding her bright orange bacteria. It forms a sticky consistency best described as “snot,” she said. This gooey, mucous-like environment globs together and protects communities of bacteria.
This can become problematic in hospitals, when patients are connected long term to silicone tubes like catheters. In rare cases, biofilm can attach and grow – causing otherwise harmless bacteria to become infectious. It can also prevent antibiotics from reaching patients, Pillay said, which makes these infections particularly challenging.
“Water doesn’t interact well with it,” Waits said, “but my phage is very effective at getting through the biofilm and infecting the bacteria by hijacking the cell machinery and replicating. It’s very good at what it does.”