Seminar: Paula V. Welander, July 10th 2023 1PM EDT

Membrane biosynthesis in archaea

Dr. Paula V. Welander

University of Stanford

July 10th 2023, 1PM EDT

Livestream at: https://go.wisc.edu/60k0g0

Zoom registration at: https://go.wisc.edu/453g11

The most striking biochemical distinction of the archaea, microbes that are phylogenetically distinct from bacteria and eukaryotes, is the chemical and structural composition of their lipid membranes. While bacteria and eukaryotes primarily have lipid bilayers composed of fatty acid chains ester linked to glycerol-3-phosphate, archaeal membranes are composed of isoprenoid-based chains ether linked to glycerol-1-phosphate. In addition, several archaeal species fuse their membrane bilayers to generate monolayers that can be further modified with the addition of pentacyclic rings, methylations, and cross-links across the lipid monolayer. All these membrane modifications are thought to occur as a response to harsh environmental conditions inhabited by many archaea – high temperatures, pH fluctuations, and nutrient limitations. However, links between environmental conditions and archaeal membrane modifications have been difficult to make for a variety of reasons including the difficulty in culturing these organisms, the paucity of molecular and genetic tools to manipulate these organisms, and a lack of understanding of the biochemical and regulatory pathways involved in the synthesis and modification of archaeal membranes. Here, I will explore recent discoveries in archaeal membrane biosynthesis and the impact physiological conditions have on the synthesis of these unique membranes in these fascinating microbes.