Just a few days ago, an article appeared in the journal Science announcing a major breakthrough: artificial transporter proteins that can carry individual atoms across the membrances that protect human cells. Clearly chemicals can pass through the barrier that protects human cells, but until now, scientists have not understood the mechanism by which certains proteins make this possible.
According to a report in ScienceDaily, a team of reseachers set out to create articifical transporter proteins and understand how they work, with the idea of engineering a new class of proteins. The work was carried out by researchers at Dartmouth College, the University of California-San Francisco, Massachusetts Institute of Technology and National Institute of Science Educational and Research in India.
Multidisciplinary approach cracks the code
The interests and background of co-lead researcher Gevorg Grigoryan of Dartmouth tell much of the complexities invovled. Grigoryan is an assistant professor of computer science and also serves as an adjusct asisstant professor in biological sciences. Commenting on his interests in his Dartmouth bio, he says:
I am inspired by proteins. I would like to understand how each protein's function is encoded in its molecular structure and amino-acid sequence. This is a highly interdisciplinary pursuit, involving concepts from biology, physics, mathematics, computer science, and chemistry.
According to the report, the team developed new computational techniques to model the necessary molecular physics, which allowed them to build a transporter protein through computer simulation. The simulations pointed to which amino-acid building blocks should comprise the new transporter, so that it would carry ionic atoms of metal zinc in one direction across membranes, while pumping protons in the other.
Once simluations were carried out, the team went to the lab to create the protein, which was dubbed a "rocker," since it was expected to "rock" between two alternating states, allowing it to drive atoms through, according to report.
Grigoryan told ScienceDaily, "To our great excitement, experiments showed that Rocker did indeed transport zinc and protons and it did, in fact, rock between two states just as designed. Further, Rocker showed great selectivity, not transporting ions of calcium, another design feature."
While the findings are in and of themselves an incredible discovery, the work also shows the growing importance of interdisciplinary pursuits and increasingly productive use of computer simulations.