For two students at Greater Latrobe Senior High School, biological discovery began with dirty french fries retrieved from the cafeteria floor and dirt scooped from their back yards.
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Jake Falbo, left, and Joe Gross, students at Greater Latrobe Senior High School, join University of Pittsburgh professor Graham Hatfull in the biological sciences laboratory. Falbo and Gross are authors of a research article about two new species of viruses. |
From these and other sources, senior Joe Gross and junior Jake Falbo were able to isolate two new species of viruses that infect bacteria. Working with researchers at the University of Pittsburgh, they then analyzed the genetic makeup of the viruses, which they dubbed Barnyard and Rosebush.
And that's how Gross and Falbo became authors of a research article that appeared April 18 in Cell, a leading scientific journal.
"This is, like, totally different from what you do in the classroom," the 17-year-old Falbo said.
The viruses, called bacteriophages or, simply phages, infect and kill only bacteria, not humans.
Phages are the most abundant biological entities on the planet, numbering an estimated 10 million trillion trillion. There may be 100 million different species.
Scientists have long speculated that phages might be an alternative to antibiotics for treating bacterial diseases.
But the paper in Cell, which included analyses of eight phage species in addition to the two found by Gross and Falbo, makes it clear that much remains to be learned about the wildly varied genetic makeup of these viruses.
All 10 of the phages are those that infect only mycobacteria, a genus that includes bacteria that cause tuberculosis and leprosy. Half of the genes in those 10 phages have never been seen before, said Graham Hatfull, a Pitt biologist and lead author. Of the remaining half of the genes, 80 percent aren't found anywhere but in these and four previously analyzed phages, also from mycobacteria.
Take any pair of the phages and you'd find they have only 2 percent of their genes in common, he added.
"This new report shows that we are just starting to appreciate phage diversity," Forest Rohwer, a biologist at San Diego State University, wrote in an accompanying commentary. Based on the findings from the 14 mycobacteriophages to date, it appears scientists have examined just 0.00002 percent of all phage genes.
Though phages don't infect humans, one phage gene uncovered in this study might be implicated in a human disease, Hatfull said. The gene is similar to one in humans that makes a protein called Ro. The autoimmune disease called lupus occurs when the body produces antibodies that attack Ro.
Some researchers have suggested that bacterial infections can trigger lupus, but the link has yet to be proven. Based on these latest findings, however, the inability to confirm the link is understandable -- it's may not be the bacteria that triggers lupus, but perhaps a phage that only some bacteria contain.
Falbo and Gross became involved in the study almost two years ago. Deborah Jacobs-Sera, a biology teacher at Latrobe Junior High who works with gifted students, had approached the two about working on a senior project, which is required for graduation. Her brother, William R. Jacobs Jr., a microbiologist at the Albert Einstein College of Medicine in Bronx, N.Y., collaborates with Hatfull and arranged a visit for the students.
"I really thought we would go down for a day of show and tell," Jacobs-Sera said. But when they arrived in Hatfull's lab, he proposed that Gross and Falbo help identify new phages.
Hatfull, who last year was selected as a Howard Hughes Medical Institute professor and given a $1 million, four-year grant for his innovative education efforts, said discovering and analyzing new phages is an ideal way both to teach science and to begin the huge task of studying phages.
Gross and Falbo collected dirt samples from a variety of places and added bits of the gunk to bacteria cultures that they grew at the high school. If a phage is present, the virus kills the bacteria and eventually causes holes, or plaques, to grow in the bacterial films.
They would remove the plaques, dilute them and check for purity. They would then take the phages to Pitt, where Hatfull's lab members would sequence the phages' DNA. Falbo and Gross compared the DNA sequences to those already catalogued in computer databases.
The work often kept the pair going from the last bell of the school day, at 2:37 p.m., until 7 p.m.
The Cell paper, which lists Pitt biologists Roger Hendrix and Jeffrey Lawrence and Albert Einstein's Jacobs among its authors, also includes a phage discovered by Lauren Keenan, a high school student in Pelham, N.Y.
Two other Latrobe students, Melissa Fritz and Andrew Hryckowian, have since joined the ongoing study and Hatfull has expanded the program to other high schools.
Byron Spice can be reached at bspice@post-gazette.com or 412-263-1578.
