Karst Laboratory
University of Florida, Dept. of Molecular Genetics and Microbiology
Meet our team
Stephanie M. Karst, PhD
Professor & Principal Investigator
skarst@ufl.edu
Stephanie Karst is a Professor in the Department of Molecular Genetics & Microbiology. Her laboratory investigates how maternal and microbial signals shape health during early life, with a particular focus on bile acids as signaling molecules linking maternal physiology, the microbiome, neonatal immunity, and developmental programming. The lab combines virology, microbiology, metabolism, developmental biology, and mouse genetics to uncover mechanisms through which the early-life environment influences both immediate and long-term health.
Haley Wilt
MD-PhD Student
NICHD F30 Predoctoral Fellowship
Haley received her BS in Biochemistry from Washington College in 2021. She spent a gap year at the National Cancer Institute in Frederick, MD in the lab of Dr. Yun-Xing Wang studying RNA structure using x-ray crystallography. She joined the MD/PhD program at UF in 2022 and started in the Karst lab in 2024. Her studies now focus on the role of maternal bile acids and the metabolic programming of offspring.
Hannah Hayakawa
Undergraduate Researcher
Hannah is majoring in Microbiology & Cell Science. She joined the University of Florida in 2024 and the Karst Lab in Fall 2026. She is studying whether milk bile acids regulate insulin and GLP-1 production in early life.
Elizabeth Chapman
Undergraduate Researcher
Elie is majoring in Public Health. She joined the University of Florida in 2025 and the Karst Lab in Summer 2025. She is investigating whether milk bile acids regulate thermogenesis in offspring.
Jolie Martinez
Undergraduate Researcher
Jolie is majoring in Chemical-Biological Engineering. She joined MIT in 2025 and the Karst Lab in Summer 2026. She is studying whether milk bile acids cause adipocyte hypertrophy in response to metabolic stress.
Sarayu Vanga
Undergraduate Researcher
UFCOM University Scholar
Sarayu is majoring in Biology and Public Health. She joined the University of Florida in 2024 and the Karst Lab in Fall 2024. She is studying the role of the bile acid receptor TGR5 in milk bile acid-mediated growth promotion during maternal high-fat diet feeding.
Rishi Gadikota
Undergraduate Researcher
Rishi is majoring in Microbiology and Economics. He joined the University of Florida in 2023 and the Karst Lab in Fall 2023. He assists Haley with metabolic cage data collection and processing for studies of early-life metabolic programming.
Lufuno Phophi, PhD
Postdoctoral Fellow, 2023-2025
Current position: Focusing on family
Zhengzheng Hu PhD
Postdoctoral Fellow, 2023-2025
Current position: Postdoctoral Fellow, University of Florida
Emily (and Haku!) Helm, MD-PhD
MD-PhD Student, 2018-2022
Honors: NIAID F30 and UF Oral Biology T90
Current position: Pathology Resident, University of Washington School of Medicine
Neha Iyer
Undergraduate Researcher, 2021-2024
Honors: UFCOM University Scholar
Joyce Morales, PhD
PhD Student, 2021-2025
Honors: UF BMID T32 and McKnight Doctoral Fellow
Current position: Postdoctoral Fellow, University of Florida
Marco Grodzki, PhD
Assistant Scientist, 2018-2024
Current Position: Assistant Scientist, University of Florida
Meera Nair
Undergraduate Researcher, 2021-2025
Honors: UF SIMR Intern
Current Position: MD Candidate, Wake Forest University School of Medicine
Alumni
Mallory Cadiz
Undergraduate Researcher, 2024-2026
Current position: PhD Candidate, University of Florida
Amy (and Samuel!) Peiper, MD-PhD
MD-PhD Student, 2020-2024
Honors: NIAID F30 and UF BMID T32
Current Position: Neurology Resident, University of Colorado, Anschutz
