Chem Bio Seminar – Prof. Laura Dassama (Stanford University)

1315 Seminar Hall
@ 3:30 pm - 4:30 pm

Prof. Laura Dassama

Title: Deciphering the molecular mechanisms of lipid trafficking in bacteria


Lipids, including sterols, are important for mammalian cell physiology. These molecules form part of membranes and modulate their fluidity, thereby maintaining membrane integrity, providing tolerance to stress, promoting fusion events, etc. Whereas decades of research have provided molecular insights into eukaryotic sterol lipid synthesis, transport, regulation, and function, a similar understanding of sterols is lacking for bacteria. It is known that some bacteria make sterols de novo, and others use it to establish pathogenesis. Moreover, gut microbiota interactions with sterols can alter host lipid metabolism and profoundly impact human health. Despite the preponderance of research about microbial interactions with these lipids, missing are molecular insights into how the interactions occur and how they are regulated. We begin to address this knowledge gap by identifying the first examples of transporters for bacterial sterols. We provide structures and molecular mechanisms for these proteins and note that they differ substantially from eukaryotic sterol transporters. The widespread presence of homologs in bacterial genomes suggests that sterol trafficking is not as rare as once thought. Guided by structural insights, we now aim to uncover the molecular details that govern bacterial engagement with sterol lipids, which we posit will reveal novel targets for therapeutic interventions in bacterial colonization and aberrant sterol metabolism.


Laura obtained her Bachelor of Science in Biochemistry from Temple University in 2007. She then completed graduate studies at The Pennsylvania State University in 2013 under the mentorship of Profs. Marty Bollinger and Carsten Krebs. Laura performed postdoctoral training in the laboratory of Prof. Amy Rosenzweig at Northwestern University, where her research focused on elucidating the transport and biosynthetic mechanisms of peptidic natural products. In 2017, Laura moved to the laboratory of Dr. Stuart Orkin at Boston Children’s Hospital, Harvard Medical School, and Dana-Farber Cancer Institute, where she worked to biochemically characterize regulators of hemoglobin. Laura moved to Stanford as an Assistant Professor of Chemistry and Sarafan ChEM-H Institute Scholar in 2018. In 2022, she received a secondary appointment in the Department of Microbiology & Immunology at Stanford School of Medicine.

Laura is a beer aficionado who enjoys brewing (and drinking) Belgian beers. She is a huge fan of Trappist beers and has visited 10 of the 14 Trappist breweries.

Host: Prof. Andrew Buller