Northwestern University Feinberg School of Medicine
Research

Faculty Profile: Karla Satchell, PhD, Professor of Microbiology-Immunology

Seth Corey, MD, MPH

Karla Satchell, PhD, professor of Microbiology-Immunology, studies bacterial MARTX toxins and their role in the pathogenesis of Vibrio species, pathogens that can cause food-borne infections. 

She became interested in bacteria toxins as technician at the University of Washington, where she worked to purify and study the adenylate cyclase toxin of Bordetella pertussis, the bacterium that causes whooping cough. 

Later, her experience learning microbiology as a graduate student and postdoctoral fellow made her unusual among toxin biologists: her lab conducts not only biochemical and cell biology experiments, but also studies how these mechanisms impact infection. 

Q&A

What are your research interests?

My primary interest is in the mechanism of action of bacterial protein toxins and how production of these toxins contributes to the ability of bacteria to cause disease.

What is the ultimate goal of your research?

To understand the molecular basis of infection by Vibrios to improve surveillance and monitoring of this reportable disease as its impact increases in the U.S. due to climate change, as outbreaks of Vibrios bacteria commonly occur in warm climates.

How does your research advance medical science and knowledge?

Our mechanistic work has impacted many different diseases. The proteins that we have discovered and characterized turn out to be found in other important pathogens. These have become targets for development of small molecule therapeutics, including antibiotic-associated colitis, which causes 250,000 cases of hospital-acquired disease annually. 

These proteins have also been used to generate novel reagents to enhance biomedical research. Finally, our newest discovery suggests that at least one of these proteins could be used to treat cancer.


What types of collaborations are you engaged in across campus (and beyond)?

I have a collaboration with David Gius, MD, PhD, professor of Radiation Oncology and Pharmacology, on the Ras protein. His lab assisted with reagents and assays that were integral to our recent characterization of one of our proteins as a Ras protease (published last June in Nature Communications) and another as activating apoptosis (just accepted in Infection and Immunity). 

We have a new collaboration with Spiro Getsios, PhD, assistant professor of Dermatology and Cell and Molecular Biology, to develop a novel reagent to specifically treat skin cancer and other skin diseases. 

I have also a long-term active collaboration with Wayne Anderson, PhD, professor of Biochemistry and Molecular Genetics, on the structural biology of the proteins we study. Our structural studies now also encompass a collaboration with Vadim Gaponenko, PhD, at University of Illinois at Chicago (UIC), who is working with us on nuclear magnetic resonance structures.

Across the nation, I collaborate with many biochemists and cell biologists. A pending paper in Nature Communications, on discovery of a novel phospholipase that inhibits autophagy, was conducted in collaboration with Gilbert Di Paolo, PhD, at Columbia University. He specializes in the role of lipids in endocytic trafficking, and his input was essential to the novel findings of this forthcoming paper. 

This paper also required assistance on surface plasmon resonance from Wonhwa Cho, PhD, at UIC. Finally, we have collaborated more than 10 years with mass spectrometry specialist Joseph Loo, PhD, at University of California, Los Angeles, who does work with us on defining posttranslational modification.

Who makes up your research team and what role does each individual play in your research?

My group is generally a mix of graduate students, postdocs and technicians. I currently have in my group two students, two post docs and an infectious diseases fellow.

About 75 percent of my graduate students and post docs have been foreigners coming from Korea, India, Italy and Germany. 

Where have you recently published papers?

I have already published 10 papers in 2015! One paper is in Nature Communications with another pending final review.

Other papers have been published in high quality microbiology journals including Infection and Immunity, Cellular Microbiology, Molecular Microbiology and mBio.

I have also published extensively in Proceedings of the National Academy of Sciences, EMBO Journal and PLoS Pathogens.

Which honors are you most proud of and why?

I am most proud of my award from the Burroughs Wellcome Fund (BWF) as an Investigator in the Pathogenesis of Infectious Diseases.

Recipients of this award are assistant professors who have already demonstrated exceptional talent as independent researchers. The BWF investigators have, as a pool, become the distinguished leaders of microbiology.

I am also proud of being inducted into the American Academy of Microbiology. This society is the premier society of our field and election recognizes outstanding research achievement in the field.

Who inspires you? Or, who are your mentors?

At Northwestern my most important mentor has been Tom Hope, PhD, professor of Cell and Molecular Biology, who for a brief period of time was housed in swing space in the lab next to mine.

Although we moved on to new permanent labs, we still meet for lunch often, where I can freely discuss how I am managing my lab, publication and funding issues and career concerns. I think it is very important as a faculty member to have a mentor outside of one’s own faculty.