Fig. 4: Cryo-EM structure of CerS6 in complex with N-palmitoyl FB1.
From: Structural basis of the mechanism and inhibition of a human ceramide synthase
a, Cartoon representation of CerS6 with bound N-palmitoyl FB1 (shown as sticks; cyan carbon atoms). The cryo-EM density of the bound product is shown as a transparent cyan surface. b, Cutaway molecular surface representation, revealing that the N-palmitoyl FB1 species occupies the entire length of the central cavity. The Hox-like domain was omitted for clarity. c, Intact mass analysis of protein samples after incubation in the absence of substrates (black) or in the presence of the mycotoxin FB1 (blue) (n = 3 biological replicates). Replicate traces are provided in Extended Data Fig. 6. d, LC–HRMS detection of N-palmitoyl FB1. The EIC for its expected [M + H]+ ion is shown after incubation of the acyl–enzyme intermediate with FB1 (blue) or in the absence of the toxin (black). Inset, chemical structure of FB1. Its primary amine (salmon circle) and TCA (gray circles) groups are highlighted.
