Fig. 5: DNP-enhanced analysis of polysaccharide organization in C. auris.

a MAS-DNP of apo C. auris AR386 using the AsymPolPOK biradical (top) resulting in a 57-fold (bottom) enhancement in NMR sensitivity. The enhancement factor (ε_on/off) is calculated by comparing the intensity of spectra recorded with and without microwave (MW) irradiation. b DNP 2D ¹³C-¹³C correlation spectra of apo C. auris AR386 with 5 ms PAR recoupling time. An intermolecular cross-peak is noted between the chitin methyl group and carbon 3 of a minor β-1,3-glucan form (B^b; cyan), rather than the bulk form (B; blue). c DNP 2D ¹³C-¹³C correlation spectrum of apo C. auris AR386 measured with a longer PAR mixing of 20 ms. intramolecular correlations within chitin, mannan, and β-1,3-glucan are marked using open circles (orange, yellow, and blue, respectively). Long-range intermolecular cross-peaks between these polysaccharides are labeled. d Summary of intermolecular interactions among chitin (dark orange), β-1,3-glucan (blue), and mannan (yellow). The carbon 3 site of the special β-1,3-glucan form (B^b) is highlighted in green. Dashed lines indicate single interactions (e.g. ChMe-B^b3), while solid lines show bidirectional interactions (e.g. ChMe-B^b3 and B^b3- ChMe) to account for the direction of polarization transfer. Source data are provided as a Source Data file.