The primacy of proteins
Protein complexes -- intricately-linked bundles of proteins -- drive most biological processes, both good and bad. Proteins perform repair and maintenance of bodily tissues and enable digestion, but when a protein is formed incorrectly -- called protein misfolding -- it can lead to many degenerative diseases, including Alzheimer's, Parkinson's, and diabetes.
The better we understand proteins, the more opportunities we will have to ensure good health, optimize agricultural production, identify disease biomarkers, and develop new ways to prevent or treat diseases.
The problem is that some protein complexes are difficult to characterize. Nuclear Magnetic Resonance (NMR) spectroscopy and x-ray can do the job for certain proteins and protein complexes, but are not always useful for larger and more complicated protein complexes. That's where mass spectrometry and Dr. Vicki H. Wysocki come in.
Unraveling the complexity of protein complexes
Wysocki and her colleagues at The Ohio State University are at the forefront of researchers working to unlock the secrets of proteins. Specifically, her Wysocki Research Group is furthering scientific understanding of protein complexes -- and expanding the capabilities of mass spectrometry -- through a technique called surface-induced dissociation (SID). The goal of SID is to break down protein complexes into smaller sub-units, or sub-complexes,
Surface-induced dissociation
"Most commercial tandem mass spectrometers have collision-induced dissociation, or CID, where you collide ions into a gaseous target, as their main fragmentation method," said Wysocki. "Collision-induced dissociation involves many collisions with gas. Each collision with a low-mass gas doesn’t transfer very much energy into the complex, and these very low-energy collisions cause one protein sub-unit to start to unfold. As that protein unfoldfs, it gains surface area and it steals charge from the remaining proteins of the complex."
SID offers an attractive approach to protein fragmentation, breaking complexes down in a way that shows how the parts of the complex are connected.
"The fragments from the SID reflect the original structure, its topology, and the interface-binding strengths of that complex," noted Wysocki. "The advantage added to tandem mass spectrometry is fragmenting these large complexes in a way that the other activation methods don’t. SID gives the most complete information possible but it also benefits from working in a complementary way with other mass spectrometry techniques and other biophysical and biological measurements."
The potential impact of SID is far-reaching.
"Anybody who’s trying to understand how proteins work in living systems would benefit from SID," said Wysocki. "That could be medicine. It could be agriculture. The fields that would benefit are fairly broad, because we do fundamental work on how to better characterize protein complexes, and the protein complexes are used in any living organism of any kind."
SID is not a new technique. It was developed many years ago at Purdue University by Prof. R. Graham Cooks. However, at that time, instruments were not yet capable of analyzing very large protein complexes or polymers. Today's systems from Waters do support those capabilities, as well as providing additional orthogonal information through techniques such as ion mobility mass spectrometry, which is also critical to Wysocki's research.
"Without ion mobility we have no way to measure shape, no way to measure collision cross-section," Wysocki noted. "In our work, from small molecules all the way through these large protein complexes, the ability to measure shape is important, because it’s an orthogonal factor that lets us discriminate things better. It’s a huge help. Sometimes we use it to separate things before we fragment them, and sometimes we use it to measure things that we’ve already fragmented and see if we’ve changed the shape, or what the shape or cross-sections are of the different products."
Putting SID on her Waters SYNAPT mass spectrometer requires modification to the mass spectrometer, a collaborative effort involving the Wysocki Research Group and Waters. SID is not yet available as a commercial product.
"The fact that Waters has been so open and willing to help us has been unique," said Wysocki. In this exploratory research, Waters' focus is not the bottom line—it’s making sure that the research gets done well."
A Kentucky girlhood
Exploring the workings of complex proteins may seem a long way from Vicki Wysocki's roots in rural southern Kentucky, but learning has always been important to her.
"I always wanted to understand how things worked, and I remember going home from school, even as a first grader, and saying 'Guess what we learned?' and asking lots of questions, and having my mom say, 'Let’s look it up in the encyclopedia.'"
Wysocki's grandmother, Grace Kerr, was also a powerful influence.
"My wanting to have an education was flavored by the fact that my grandmother wasn’t allowed to finish school," she noted. "Her mother passed away, and she was asked to stay home and take care of the family, and wasn’t able to finish school. That irritated me a lot when I found out that as a little kid."
The road to eminent scholarship
After an enjoyable high school chemistry class in Kentucky with Mr. Dale Holder, Wysocki really fell in love with chemistry during a class in her freshman year at Western Kentucky University. She soon became a teaching assistant. After earning her BS in Chemistry, she moved on to Purdue University for her PhD, where Graham Cooks was a valued mentor. Postdoctoral work at Purdue and the Naval Research Laboratory was followed by professorships at Virginia Commonwealth University and the University of Arizona, where she eventually became Chair of the Department of Chemistry and Biochemistry. Wysocki joined Ohio State in 2012.
"My family always encouraged me to continue on in school, and then there was the factor that there aren’t so many women chemists, especially as you get up to the full professor ranks in academia," said Wysocki. "So being a woman in chemistry appealed to me, being a role model for other women, and showing that it’s possible to have a family and also be a professor."
She and her husband, Ron Wysocki, Senior Lecturer in Ohio State's Chemistry and Biochemistry department, have one son, Zachary. She enjoys traveling throughout the world, with Russia and Australia high on her list of countries yet to visit.
In the meantime, she's mentoring her students, running her 15-person research group, and helping other scientists figure out what makes proteins tick.
"Yesterday we met with a researcher who has made a modified cardiac protein, and is testing it in mice at this stage, and when they got their reviews back from Nature Communications, the reviewers wanted more information," she noted. "So he came to see us to see if we could help him measure the protein complex, because it looks like it could be a solution for treating heart disease.” I think we’ll see more and more researchers take advantage of this for fundamental studies, but fundamental studies that could expand very directly into clinical."
