Students Grab Gold with Bacteria-to-Blood Project
A team of Cal undergraduates has demonstrated how genetically modified E. coli bacteria might be converted into a cheap—and safe—blood substitute. The engineered product, called “Bactoblood,” addresses a global shortage of human blood for transfusions, particularly in developing countries and emergency situations, the young developers say.
“Bactoblood is universally compatible, disease-free and inexpensive, and you can reproduce it like crazy,” explains Samantha Liang, a bioengineering junior involved in the recent interdisciplinary project. “I thought it was a really great idea.”
So, apparently, did judges at the annual International Genetically Engineered Machine competition (iGEM) held last fall at MIT. Facing more than 50 undergraduate teams from 19 countries, UC Berkeley's Bactoblood squad was named one of six finalists in the prestigious synthetic biology event. Peking University won the grand prize by constructing a bacterial assembly line with potential medical and engineering applications.
The competition “really motivates a lot of people to get in the field,” says John Dueber, a postdoctoral fellow at the California Institute for Quantitative Biosciences (QB3) and an adviser to the Bactoblood group. Bactoblood “sounds crazier than it actually is,” he says.
Despite its dreaded association with serious food poisoning, the E. coli used in the Bactoblood experiment was modified to remove its toxicity and help it live longer in the bloodstream. This was accomplished using a process developed by Chris Anderson, a recently appointed assistant professor of bioengineering.
To produce Bactoblood, the students killed the DNA in the bacteria, creating what were essentially empty shells of protein. They inserted genes to produce hemoglobin, the protein in red blood cells that carries oxygen. When the substance turned red, the students knew hemoglobin was being manufactured and transporting oxygen. Further modifications were made so the bacteria could be freeze-dried to lengthen its shelf life.
The idea for Bactoblood was developed by Austin Day, a senior in chemical biology. The team included a half dozen undergraduates studying bioengineering, biochemistry and even anthropology; three high school students; and graduate and faculty advisers.
Liang's assignment was to engineer the genetic “self-kill” switch that destroyed the bacteria's DNA to ensure it wouldn't reproduce in the bloodstream. “It was like a fulltime job,” she said of her summer work.
With the competition now behind them, work on Bactoblood is on hold and the students are pursuing other projects. But the participants remain upbeat about its potential, pointing to the substantial progress they made in just a few months of lab time. “I don't see why it wouldn't work eventually,” says Liang.