“…With this aim we took a closer look at two types of cholesterol binding motifs, the so-called cholesterol recognition/interaction amino acid consensus (CRAC) motif with the L/V -X(1–5)- Y/F -X(1–5)- R/K pattern, and the reverse CARC motif with the R/K- X(1–5)- Y/F -X(1–5)- L/V pattern [ 36 , 37 , 38 ]. CRAC and CARC sites have been identified in transmembrane segments of several membrane proteins, such as G-protein coupled receptors, but also in membrane-interacting segments of several bacterial toxins and viral proteins that interact with cholesterol [ 39 , 40 , 41 , 42 ]. Moreover, in the aforementioned three RTX toxins (LtxA, HlyA and RtxA), CRAC sites have been identified in their pore-forming domains and for two of them, LtxA and RtxA, the interaction with cholesterol has been experimentally demonstrated [ 33 , 34 , 35 ].…”