People | Toprak Lab

Erdal Toprak, Ph.D.

Associate Professor · Southwestern Medical Foundation Scholar in Biomedical Research

Erdal Toprak received his Ph.D. in Computational Biology and Biophysics in 2007 from the University of Illinois at Urbana-Champaign where he studied motility mechanisms of molecular motor proteins with Paul R. Selvin. He then moved to Roy Kishony's Lab at Harvard Medical School as a postdoctoral research fellow and studied evolution of antibiotic resistance. Dr. Toprak joined UTSW in 2014.

Alan Katz, Ph.D.

Adjunct Instructor

Deniz Sezer, Ph.D.

Instructor

Deniz Sezer received his Ph.D. in Physics in 2008 from Cornell. In his doctoral work he calculated electron spin resonance spectra of a protein from atomistic trajectories generated through molecular dynamics simulations. As a postdoctoral researcher, he used molecular dynamics simulations to rationalize dynamic nuclear polarization experiments. In 2010, he became a faculty member at Sabanci University in Istanbul, where he investigated the kinetics of drug-membrane permeation. In the Toprak Lab, he focuses on the statistical inference of fitness landscapes, specifically establishing the quantitative framework for the massive-scale mutant competition experiments.

Fatma Sevde Coskun, Ph.D.

Postdoctoral Fellow

I am a postdoctoral researcher in the Toprak Lab at UT Southwestern. I received my PhD in Immunology from UT Southwestern, where I trained in the Van Oers Lab, and then worked briefly in industry. I joined the Toprak Lab in 2024 and have since worked on multiple projects while expanding my expertise in next-generation sequencing (NGS) analysis. My research includes building mutagenesis libraries of β-lactamases to study evolutionary trajectories and developing a highly efficient protocol for isolating bacteria from blood. I am also involved in one of the lab’s most exciting projects focused on blood-based cancer diagnostics. Outside the lab, I enjoy playing with my dog (despite his lack of enthusiasm), cooking, going to the movies, and oil painting.

Muhammed Sadık Yıldız, Ph.D.

Postdoctoral Fellow

I first joined the Toprak Lab as an undergraduate at Sabancı University, where I helped design and build several iterations of the original morbidostat. During my Ph.D. in Systems Biology at Harvard with Johan Paulsson, I built and ran the longest continuous culture evolution experiment to date and studied the limits of the fastest possible exponential growth. During and after graduate school, I helped Kernal Biologics develop computational tools for mRNA therapeutic payload optimization. I returned to the Toprak Lab in 2022. My current research is focused on the design of an end-to-end genomics pipeline from blood draw to diagnosis that powers our liquid biopsy program. This work led us to found Early Marker. When I'm not checking out cryptic gene annotations or staring at code, I enjoy history and fiction, in print or on screen, or in the form of real-time strategy games.

Ariq Chowdhury

Research Technician

I am a Research Technician at the Toprak Lab. I earned my bachelor's degree in biology from Texas A&M University in 2023 and am currently applying to medical school. My primary role involves coordinating participant consent and clinical sample collection across multiple UTSW clinics, as well as tracking sample metadata and monitoring collection workflows for our research study. Outside the lab, I enjoy going to the gym, travelling, and listening to any genre of music.