"It's a very complicated data analysis routine that literally generates tens of thousands of peptides that took a team of students and postdoctoral associates overseen by Hao Zhang and Michael Gross, months to analyze," Blankenship said. Hao Zhang, PhD, is a PARC research Scientist and Michael Gross, PhD, is professor of chemistry and Director of the Mass Spectrometry Resource in Arts & Sciences.
In the meantime research scientist Dariusz Niedzwiedzki, PhD, in the PARC Ultrafast Laser Facility was exciting the phycobilisome in intact megacomplexes and tracking the energy through the complex by the faint glow of fluorescencing molecules.
Typical energy transfers within the complex take place in a picosecond (a trillionth of a second), way too fast for humans to perceive. If one picosecond were a second, a second would be 31,700 years.
"PARC is one of the only places in the world that has available this sophisticated combination of experience and advanced techniques," said Blankenship, "and to solve this problem we were brought all of our expertise to bear.
"The work provides a new level of understanding of the organization of these photosynthetic membranes and that is something that a lot of people have tried to understand for a long time," he said.
"It also introduces the methodology of the crosslinking and then the mass spectrometry analysis that could potentially be applicable to a lot of other complexes, not just photosynthetic ones," he said.
"For example, enzymes in some metabolic pathways have long been thought to form supercomplexes that channel the products of one reaction directly to the next one. This technique might finally allow channeling supercomplexes to be identified in cases where the complex is only very weakly associated," he said.
|Contact: Diana Lutz|
Washington University in St. Louis