This is an archived article. For the latest news, go to the Advance Homepage
For more archives, go to the Advance Archive/Search Page.
Birge Blends Chemistry and Biology
to Shape High-Tech Future
ith some help from Bob Birge and his colleagues, a bacterium that is 3.5 billion years old may revolutionize the future of computing.
The ancient bacterium, found in salt marshes, has survived longer than any other organism on Earth, Birge says, and as a result of myriad evolutionary changes has become extremely efficient at converting light into energy.
In the past few years, Birge and his research colleagues have taken the bacterium and the light-transmitting protein it contains, bacteriorhodopsin, through a few more changes, speeding up the evolutionary process to optimize its capacity. It's a process he calls 'directed evolution.'
The bacterium's venerable age and extraordinary capacity for survival mean that Birge and other researchers can manipulate certain sections of it without killing it in the process. As a result, he has been able to adapt the protein and the chemistry that goes on inside it so that it can be used as a means of storing information by computers.
"Bacteriorhodopsin is the most cost-effective way to store data that is currently available," says Birge, the first Harold S. Schwenk Sr. Distinguished Chair in Chemistry. "We are essentially using nature to provide a mechanism for data storage."
The approach is revolutionary because the protein that is made by the bacterium and which is used to store data is so small: it would take many hundreds of protein molecules to equal the size of a single magnetic particle on a magnetic disk. The phial of amethyst gel - the purple protein set in a polymer gel - in his hand is smaller than his little finger, yet it can store twice as much textual information as the Library of Congress contains.
The search for ultra-small molecular-based electronic devices is just one of the avenues of research Birge is pursuing. Underlying each of his research interests, however, is the theme of using nature for the good of society.
"The overall theme of Bob's work is to learn from biological processes - which have had eons over which to evolve - lessons about efficiency and mechanisms, and to try to mimic those or reproduce them in an artificial system," says Harry Frank, a professor of chemistry.
For example, Birge is also working with bacteriorhodopsin to develop associative memory that mimics the human brain. As a biological substance, the protein also allows for data to be stored in three dimensions, just as it is in the human brain.
He and his fellow researchers have already produced one-of-a-kind memories for the Air Force, where they are used to collect and store satellite downlink data. "This type of memory is inexpensive and offers fast random access," says Birge.
In addition to research with practical applications, Birge also has elucidated some of the primary photochemical mechanisms that are responsible for vision - the process by which light is absorbed and ultimately converted into a neural impulse that goes to the brain.
"His contributions to understanding the molecular basis for vision have been pioneering," says Frank, who is collaborating with Birge on a project to deepen the current understanding of how, on a molecular level, plants and algae convert solar energy into chemical potential.
But the project that's closest to Birge's heart is to develop an artificial retina. It's an enterprise inspired by the experience of his mother, who was blind for the last 20 years of her life. "Loss of sight has a major impact on a person's life and ability to enjoy life," he says. "I feel we could do a lot of good in this area and I always want to be working on something that will have an impact."
The project seeks to learn from the extraordinary efficiency with which the human eye captures light in order to produce an artificial retina. "It combines the vision work I've done for decades and bacteriorhodopsin," Birge says. "What's needed now to develop medical applications of this is a chip that can be inserted into the eye," he adds, "and carry out the function of the retina by absorbing light and converting it into an impulse to the optic nerve."
"Everybody has to become somewhat of a generalist to have a high impact in science," says Birge, who holds joint appointments in both chemistry and molecular and cell biology at UConn. "The major achievements of the future will be at the interfaces of scientific disciplines."
Interdisciplinary research has not always come easy to him, however.
About eight years ago, he says, "I hit a stone wall in my research. I tried just using chemistry to optimize the protein (bacteriorhodopsin) and took it as far as I could, but it was still not good enough."
He realized he could not go any further without learning molecular biology. "So I went out and bought books and learned it," he says. "It was very painful. I felt like I was a student again."
Although interdisciplinary research and even some joint appointments in the scientific disciplines are not new to UConn, Birge is urging the University to go further, by adding more joint appointments and structuring them with equal responsibilities in each relevant department.
"It's a lot of work," he acknowledges, and so requires a lighter teaching load. But it is essential to progress in the sciences, he says. And for the sake of the scientists of the future, he says, interdisciplinary classes should be populated equally with students majoring in each field and address topics relevant to both groups. "Students," he says, "often find interdisciplinary work easier than do faculty."
A native of Long Island, Birge is no stranger to Connecticut. He attended the private Choate School (now Choate Rosemary Hall) in Wallingford and went on to Yale - where he was a contemporary of George W. Bush. He intended to major in music, but when one of his compositions won third place in an international competition, he realized that, though talented, he was not good enough to make a living as a classical composer. That's when he turned to science. He earned his Ph.D. in chemical physics from another Connecticut institution, Wesleyan University.
But Birge - whose career has included a postdoctoral fellowship at Harvard and stints of teaching at the University of California-River side and Carnegie Mellon - says it was what the University of Connecticut had to offer rather than familiarity with the state that brought him back to Connecticut.
First, he says, he was attracted to UConn by the resources the chair provides. "The endowed chair provides me with financial resources to do the kinds of experiments I would not be able to do otherwise - very high-risk projects. That's why chairs are so important - they attract people who want to do high-risk research and give them a good chance of succeeding. High-risk research is also high pay-off."
The new chemistry building was an added draw. "This building, and the other facilities UConn 2000 is putting together, shouldn't be underestimated," he says. "They are changing the campus permanently to being one that can compete internationally with the top universities
"This is the best chemistry building in the country," he adds, "and it gives us a reasonable expectation of being able to hire the best people, because facilities are so important, especially to scientists."
Yet the most important factor in coming to UConn, he says, is the potential for him to have a positive impact. He hopes to help the chemistry department and the University build a more effective research environment, not just in chemistry but in collaborative research.
The prospects look good for doing just that. Gary Epling, chair of the chemistry department, says the endowed chair enabled the University to hire in Birge a scientist with "a huge amount of intellectual capacity, outstanding ideas, and an extraordinary energy level," who complements the department's existing resources.
"Someone at that level of accomplishment is constantly bringing new scientific information to bear on a whole host of problems," Epling says. He describes Birge's enthusiasm as "extraordinarily exciting.
"You could call it infectious. And it stimulates collaboration with a lot of people to explore very fruitful directions they might not otherwise pursue."