Speaker
Description
Other authors: Lilith A. Schwartz1, Jordan O. Norman1, Sharika Hasan1, Olive E. Adamek1, Elisa Dzuong1, Jasmine C. Lowenstein1, Olivia G. Yost1, Banumathi Sankaran2,
1 Department of Chemistry, Vassar College, 124 Raymond Ave, Poughkeepsie, NY, 12604
2 Advanced Light Source, Lawrence Berkeley National Lab, Berkeley CA
Bacteroides ovatus, a commonly identified Bacteroides species in the human gut, has been shown to have beneficial effects like the suppression of intestinal inflammation. However, increased populations of B. ovatus also correlate with several autoimmune disease states, such as Systemic Lupus Erythematosus (SLE). Many host-microbe interactions depend on bacterial cell surface carbohydrates, including capsular polysaccharides (CPS). CPS from related B. fragilis has known immunomodulatory effects. While their significance is understood, CPS biosynthesis has not been well studied. In this talk, we present structural characterization of a polysaccharide deacetylase from Bacteroides ovatus (BoPDA) thought to be involved in CPS biosynthesis. High resolution crystal structures reveal an unusual metal binding strategy for the CE4 family and an atypical, non-modular domain architecture. Carbohydrate binding assays and deacetylase activity assays were used to investigate the function of the enzyme. BoPDA is the first protein CPS biosynthetic enzyme from B. ovatus to be characterized, so this work helps further our understanding of this essential bacterial process.
