Emily Lau
Editorial Director
Assistant Professor of Biology Todd Lorenz highlighted his students’ research work in sequencing bacteriophage genomes in his lecture, “Whole genome comparison of large collection of mycobacteriophages reveals a continuum of phage genetic diversity” Tuesday in the President’s Dining Room.
Lorenz started by explaining how bacteriophages are viruses that infect bacteria and describing the work he and his class contributed to a consortium project at UCLA.
The consortium consisted of more than 5,000 students and faculty members, who isolated and annotated phage genomes, from more than 74 institutions in the United States.
“This is going to be, or is at this point, the largest comparison of phage genomes to a single host strain ever performed,” Lorenz said.
The project was part of a phage hunting course at UCLA and done by undergraduate students.
Lorenz went into details about courses called CUREs, or course-based undergraduate research experiences, at the University and how they have helped students with their fields.
“This is really nice for the University of La Verne,” Lorenz said. “We have a lot of undergraduate students doing projects, doing research and trying to understand it.”
He described how the students in the class collect environment samples, purify and isolate the genomes. They later catalog the data, such as the location of the sample, size and genetic content of the phage.
Lorenz showed images of various phages that his students at UCLA have collected since 2010.
However, scientists estimate that there are more bacteria and viruses than stars on the planet and at the moment, only about 2,000 phage genomes have been sequenced, according to Lorenz.
“In just about any virus that we isolate, we actually only understand maybe 25 percent of the genome, so 75 percent of the genes that were isolated in this virus, we’ve never seen on the planet before,” Lorenz said. “They can have a whole wealth of functions that can be beneficial to us; we just don’t know it yet.”
He pulled up the Actinobateriophage Database, a website that collects data associated with mycobacteriophage discoveries and showed live statistics of the number of sequenced phages that are currently documented.
“I think it’s interesting that of the (bacteriophages) he is studying right now, that’s not all of the bacteria and viruses in the world,” sophomore child development major Heidi Park said. “There’s so much more to explore.”
Lorenz continued by discussing the diversity among the bacteria and viruses and how it is caused partly by the continuing evolutionary arms race between the two, with stronger strains overcoming each other.
Bacterium levels are held at a certain level because the rate at which they are infected by phages is so quick that about half of the population is killed every day, Lorenz said.
He showed the similarities and differences between different genomes with dot plots that compared phage clusters and singletons.
To keep the information simple, he left out complicated mathematics and technical details.
“I thought it was a little complicated because I’m not a biology major, but it was good that (Lorenz) explained it well,” junior accounting major Megan Hodgson said.
After talking about his work at UCLA, Lorenz began recognizing the work that students in his classes at the University have done.
Lorenz and his students isolated a bacterium called Bacillus pumilus, which is known to cause foodborne illnesses.
He concluded with the idea of phage hunting and how it can be done in a classroom at the undergraduate level, even with high school students.
“There have been students at a whole wide variety of institutions that have been taking part in this discovery process and they do feel an ownership to the projects,” Lorenz said. “This has been a discovery process that leads to knowledge and publications.”
Emily Lau can be reached at emily.lau@laverne.edu.
