An anomalous abundance of tryptophan residues in ceramide synthases based on analysis of all membrane proteins in the Swiss-Prot database.

The relationship between membrane proteins and the lipid constituents of the membrane bilayer depends on finely-tuned atomic interactions, which itself depends on the precise distribution of amino acids within the 3D structure of the protein. In this regard, tryptophan (Trp), one of the least abundant amino acids, is found at higher levels in transmembrane proteins where it likely plays a role in helping anchor them to the membrane. We now re-evaluate Trp distribution in membrane proteins using all known proteins in the Swiss-Prot database and confirm that it is somewhat higher (∼1.

Computational design and molecular dynamics simulations suggest the mode of substrate binding in ceramide synthases.

Until now, membrane-protein stabilization has relied on iterations of mutations and screening. We now validate a one-step algorithm, mPROSS, for stabilizing membrane proteins directly from an AlphaFold2 model structure. Applied to the lipid-generating enzyme, ceramide synthase, 37 designed mutations lead to a more stable form of human CerS2.