Blake Wiedenheft of Fort Peck was lead author of a paper explaining the SsDps protein. The paper appeared recently in the weekly journal, Proceedings of the National Academy of Sciences. Mark Young from MSU, a co-author on the paper, provided the photos and art that ran on the cover.
"This protein was isolated from Sulfolobus solfataricus, a heat-loving archaea that thrives in acidic hot springs like those found in Yellowstone National Park," said Wiedenheft who discovered the protein while looking for another.
Scientists divide life into three domains: eucaryotes (plants, animals and humans), bacteria and archaeal. Archaeal life used to be confused with bacteria, but it is now recognized as a separate domain of life. Understanding the biochemistry of the archaea may be used to understand more complex systems such as eucaryotes, Wiedenheft said.
Trevor Douglas, Wiedenheft's advisor and co-author of the paper, said the newly found protein builds a tiny cage-like structure, which it uses to isolate and detoxify iron and hydrogen peroxide. Other proteins use a similar approach, but this was the first time such a protein was found in one of these heat-loving microbes.
Wiedenheft found the new protein while running biochemical tests for Douglas. Douglas wanted to find a cage-forming protein that would be stable in high temperatures and asked Wiedenheft to look for iron-storage proteins. Wiedenheft found the SsDps instead. The new protein uses iron to detoxify hydrogen peroxide, resulting in the formation of water.
Hydrogen peroxide is a familiar sight on store shelves, but it can be highly toxic when it occurs in nature, Douglas said. Its byproducts are even more toxic. Hydrogen peroxide, in the presence of iron, changes and damages DNA, but the new protein neutralizes that activity.
Wiedenheft's discovery is significant for scientific and non-scientific reasons, Douglas continued. Not only does it demonstrate the "fantastic" opportunities for interdisciplinary research at MSU, but it has enormous implications for understanding oxidative stress in higher organisms, which is associated with diseases ranging from heart disease to Alzheimer's.
Wiedenheft said scientists believe archaeal life is more closely related to eucaryotes than bacteria, so they may be able to learn about higher organisms by studying archaeal life.
"You can often take what you learn from simple cells and sometimes apply that to understand human diseases and more complex processes," Wiedenheft said.
The journal publishing Wiedenheft's paper is one of the world's most cited multidisciplinary scientific publications. Founded more than 90 years ago, it publishes research findings, commentaries, reviews, perspectives, colloquium papers and actions in biological, physical and social sciences.
Wiedenheft's paper appeared July 15 in the online version of the journal. His paper also ran in the printed version on July 26.
Evelyn Boswell, (406) 994-5135 or firstname.lastname@example.org