Group Members
Yitong (Lexie) Li, Ph.D.
Postdoctoral Fellow
yitong_li@hms.harvard.edu
Growing up in southeast China, Yitong (Lexie) started her academic journey as an undergraduate at Zhejiang University, China. She transferred to Cornell University, NY, US, in her junior year and earned dual B.S. degrees in food science. She joined Dr. Rui Hai Liu’s Lab at Cornell where she studied the molecular mechanisms of action of natural bioactive compounds for metabolic syndrome prevention and earned her Ph.D. there. Her dedication as a teaching assistant and student mentor was recognized with the Outstanding Teaching Assistant Award from Cornell University’s College of Agriculture and Life Sciences. Lexie’s academic contributions and leadership have also been honored with many awards, including the Kosi Award, the Institute of Food Technologists Feeding Tomorrow Fellowship, and the Vitasoy & Lo Fellowship.
Outside of the lab, Lexie enjoys board game nights with friends, cooking and exploring new foods, working out, and spending time with her cat.
Po-Hsun Fan, Ph.D.
Postdoctoral Fellow
po-hsun_fan@hms.harvard.edu
Growing up in Taiwan, Po-Hsun began his academic journey as an undergraduate researcher at National Taiwan University. After earning his B.S. degree in 2016, he fulfilled his one-year military service before joining Dr. Hung-wen (Ben) Liu’s research group at the University of Texas at Austin (UT Austin), where he completed his Ph.D. in 2024. During his doctoral studies, Po-Hsun specialized in natural product biosynthesis and mechanistic enzymology. As a member of the Devlin Lab, Po-Hsun now investigates bacterial enzymology within the gut microbiome, focusing on its impact on human health and disease.
Outside the lab, Po-Hsun enjoys exploring libraries, museums, parks, and Boston’s vibrant restaurant scene with his family.
Kate Kostenkova, Ph.D.
Postdoctoral Fellow
kateryna_kostenkova@hms.harvard.edu
Kate is a native of Ukraine and received her B.S. in Chemistry with a minor in Biology from Whitworth University in Spokane, Washington, in 2018. She then moved to Fort Collins, Colorado, to pursue a Ph.D. in Chemistry under the mentorship of Prof. Debbie Crans. Her graduate research focused on the synthesis, NMR, and electrochemical characterization of bioactive redox molecules, including vanadium(V) catecholate complexes and menaquinone derivatives. Following her Ph.D., Kate joined the lab of Prof. Courtney Aldrich at the University of Minnesota as a postdoctoral fellow. Her work there centered on the synthesis of rifamycin analogs targeting multidrug-resistant tuberculosis.
Kate’s research and leadership have been recognized through several honors, including being named a 2022 DARPA Riser, receiving the Dissertation in Chemistry Award, and being selected as a 2024 CAS Future Leader Top 100. Outside the lab, Kate enjoys running, rock climbing, reading, and baking sourdough bread.
Jasmine Walsh
Chemical Biology Ph.D. Student
jasminewalsh@g.harvard.edu
After growing up in Southern California, Jasmine got her B.S in biochemistry at Oakwood University in Huntsville, AL. During her time at Oakwood, she did summer research internships at Loma Linda University and Boston University. She then did a post-baccalaureate program in Elizabeth Grice’s lab at the University of Pennsylvania. Her project centered around utilizing antimicrobials produced from the skin microbiome to inhibit the growth of MRSA.
Jasmine enjoys spending time with her friends, traveling, meditating, and taking care of her plants.
Melissa Tran
Biological and Biomedical Sciences Ph.D. Student
melissatran@g.harvard.edu
Originally from Illinois, Melissa received her B.A. in Molecular and Cellular Biology from Harvard College in 2019. As an undergraduate and lab technician, she worked in Dr. Aleksandar Kostic’s lab studying the ability of gut microbes to stimulate pancreatic development and attenuate diabetes symptoms. She is excited to be co-mentored in the Devlin and Huh labs, where she will study the role of gut bacterial metabolites in guiding host immunology and neurobiology.
When not in lab, Melissa enjoys painting, dancing with her troupe, and making and eating soup.
Cecilia Kim
Biological Sciences in Public Health Ph.D. Student
cecilia_kim@g.harvard.edu
After growing up in Vancouver, Canada, Cecilia received her B.A. in Chemistry from Princeton University in 2023. At Princeton, Cecilia worked in Dr. Robert Knowles’ lab, where she studied the use of light-driven reactions in the synthesis of macrocyclic peptides and contra-thermodynamic isomerization of olefins. Cecilia joined the Devlin Lab in 2024, and she is excited to study the effect of gut bacterial metabolites in mediating microbe-microbe and microbe-host interactions.
Outside the lab, Cecilia enjoys reading, taekwondo, and exploring Boston’s bookstores and restaurants with her friends.
Kelly O’Conor
Chemical Biology MD/PhD Student
kellyoconor@hms.harvard.edu
Kelly grew up in Cleveland, Ohio and received her B.A. in Neuroscience and Linguistics at Northwestern University where she worked in Dr. Catherine S. Woolley’s lab studying the mechanisms and metabolism of neurosteroid estrogens. After college, Kelly was an NIH Postbaccalaureate Research Fellow in Dr. Nora Volkow’s lab where she characterized opioid pharmacokinetics in the CNS and developed novel PET radiotracers for pre-clinical neuroscience research. In 2022, Kelly began her MD-PhD at Harvard Medical School, and in 2025, she joined the Devlin lab where she is excited to explore how microbes influence endogenous steroids in human health and disease.
Kelly spends her free time making art, dancing on the esplanade, and frequenting Boston’s local Irish pubs.
Sydney Abelson
Biological and Biomedical Sciences Ph.D. Student
sydney_abelson@g.harvard.edu
After growing up in South Pasadena, California, Sydney earned her B.S. in Microbial Biology from the University of California, Berkeley in 2023. As an undergraduate in Dr. Britt Koskella’s lab, she studied bacteria-phage dynamics in the phyllosphere, focusing on how competition between plant pathogens shapes disease progression and phage biocontrol efficacy. She then went on to Dr. Elliot Stieglitz’s lab at UCSF as a Junior Specialist, where she developed targeted and immune-based therapies for Ras-driven leukemias. Drawn back to host-microbe interactions, she joined the Devlin Lab in 2026 as an NSF Graduate Research Fellow to study how gut bacterial metabolites shape host immunity.
Outside the lab, Sydney enjoys traveling, testing new recipes, adding to an ever-expanding home library, and working her way through Boston’s restaurants one menu at a time.
Pray Miao
Biological and Biomedical Sciences Ph.D. Student
pray_miao@fas.harvard.edu
Originally from Zhejiang, China, Pray earned his B.S. in Microbiology and MCD Biology from the University of Washington (Seattle) in 2023. As an undergraduate researcher in Dr. Joseph Mougous’s lab, he studied the complex interactions between gut commensal bacteria with a focus on the targeting and specificity determinants of interbacterial antagonism systems. He then pursued an M.P.H. at Yale University, where he also worked as a research assistant in Dr. Eduardo Groisman’s lab. There, he expanded upon his research interest in the gut microbiome by investigating the genetic regulation of gut colonization factors. Pray joined the Devlin Lab in 2026 and is excited to explore the interplay between gut bacterial metabolites and host physiology.
Outside of the lab, Pray enjoys visiting museums, traveling, watching movies, trying new restaurants, and playing video games.
