Biophysical Society Conference | Tahoe 2024

Molecular Biophysics of Membranes

Poster Abstracts

24-POS Board 16 CHARACTERIZATION OF FRANCISELLA TULARENSIS LIPIDS Tugba N. Ozturk 1 ; W. F. Drew Bennett 1 ; Timothy S Carpenter 1 ; Helgi I Ingolfsson 1 ; 1 Lawrence Livermore National Laboratory, Physical and Life Sciences Directorate, Livermore, CA, USA Francisella tularensis (Ft) is a highly pathogenic species of gram-negative bacteria, capable of effectively invading host cells and suppressing the host immune system to facilitate infection. Ft lipids exhibit a unique tail-length asymmetry; the most abundant Ft phospholipids have acyl chain lengths of C24:0-C10:0, which is significantly more asymmetric compared to, for example, phosphatidylcholine lipids in budding yeast membranes, which have acyl chain lengths of C16:1 C16:1 or C18:1-C16:1. Characterizing Ft’s unique tail-length-asymmetric lipids is essential to understand Ft pathogenesis. We hypothesize that when invading mammalian membranes, unique Ft lipids significantly alter the host membrane properties. In this study, we will carry out coarse-grained and all-atom molecular dynamics simulations to test this hypothesis by contrasting and comparing structural properties of Ft, Ecoli and mammalian membranes and studying how the asymmetric incorporation of Ft lipids into mammalian membranes alters their properties. By investigating the molecular mechanism of Ft’s unique tail-length-asymmetric lipids, we hope to identify novel Ft countermeasures that achieve specificity by targeting Ft’s unique tail-length-asymmetric lipids.

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