NEW ORLEANS — University of New Orleans biology professor Wendy Schluchter has received a nearly $750,000 Department of Energy grant to study and deconstruct the fluorescent pigmentation process of photosynthetic microbes called cyanobacteria, once referred to as blue-green algae.
The deciphered details of that pigmentation process, Schluchter said, could be used to track proteins in order to study various diseases in mice models and in cultures of human cells, or that could be used to engineer increased biofuel production by cyanobacteria.
Schluchter, chair of UNO’s biological sciences department, has been awarded a three-year, $749,930 DOE grant to further her research.
Cyanobacteria are found in all types of environments and play a critical role in the global carbon cycle, Schluchter said. They also are a source for biofuels, a more environmentally-friendly fuel source.
These organisms harvest light using huge antenna complexes composed of specific proteins carrying pigments that give them brilliant colors from orange, pink, purple and blue. The ability to change pigment also changes the wavelengths of light available for photosynthesis, Schluchter said. Most organisms are competing for available light.
This project will study a subset of the bilin lyase enzymes that are responsible for the extensive pigment diversity of cyanobacteria, contributing to their wide adaptability to various light and nutrient environments from land to ocean.
“I’m studying a group of proteins that harvest light for photosynthesis in cyanobacteria and trying to characterize the enzymes required to add pigments to these proteins,” Schluchter said. “We are going to study a unique set of these enzymes and try and solve the structure of these enzymes to understand the biochemistry of the pigment ligation reaction.”
Schluchter, the principal investigator on the research, is working with University of Illinois at Chicago professor Xiaojing Yang, a structural biologist, on the project.
Schluchter’s Ph.D. student, Xindi Liu, who is in UNO’s integrative biology program, will travel to UIC to learn techniques in protein structure determination and analysis.
“The mechanistic understanding to be gained from this research will lay the groundwork for designing artificial photosynthetic light-harvesting systems that can be used for applications such as biofuel production,” Schluchter said. “And it will set the stage for developing tool enzymes for fluorescent protein production that can be used in all types of biomedical research to study disease processes.”
Phycoerythrin is the specific protein that Schluchter is studying. It’s currently being used as a versatile and stable fluorescent protein with many research applications, she said.
“Our research may eventually allow it to be synthesized inside human cells to ‘tag’ any protein we want to study in the cells and follow it due to its fluorescent properties,” Schluchter said. “Often when studying diseases, we find out that many proteins are not trafficked properly in cells. They accumulate where they aren’t supposed to be, so having this technology will allow us to track proteins in cells.”