Distribution and functions of hopanoid lipids in plant-microbe symbiosis

Abstract:
Life is powered by carbon and nitrogen, and the exchange of these elements is a common basis for plant-microbe symbiosis. Among the genes common to nitrogen-fixing symbionts of plants are genes encoding enzymes for biosynthesis of hopanoids, an unusual class of steroid-like bacterial lipids. However, despite their broad distribution, how and whether hopanoids make unique contributions to the symbiotic niche is unclear. Our data suggest that hopanoids participate in the early stages of the B. diazoefficiens-legume interaction by promoting bacterial motility and signal secretion. Legumes inoculated with hopanoid-deficient strains also contain a higher proportion of disorganized nodules with primarily dead bacteria. These results suggest that hopanoids fulfill key roles in soil navigation and survival within plant tissues.

About the Speaker:
Dr. Belin is a bacterial cell biologist who is enthusiastic about the mechanisms of beneficial bacteria-eukaryote symbiosis. She started her research career doing computational biology as an undergraduate at the University of Notre Dame, where she studied the molecular evolution of bacterial actin-like proteins with Dr. Holly Goodson. She then completed her PhD research at UCSF with Dr. Dyche Mullins, applying quantitative microscopy and genetics to develop tools to label nuclear actin filaments in mammalian cells and identified a new link between actin and the DNA damage response. She switched fields to environmental microbiology and plant-microbe interactions during her postdoc with Dr. Dianne Newman at Caltech. Currently, Dr. Belin runs a research laboratory that examines the roles of bacterial lipids in plant-microbe symbiosis and in bacterial membrane homeostasis. More information on her lab can be found at https://www.belinlab.org

Contact

Sohini Guhu & Liana Burghardt
svg5863@psu.edu, liana.burghadt@psu.edu