Figure 1. Molecular modeling of the interaction of CdtC^wt and cholesterol.

(A) Schematic representation of a partial sequence of the CRAC-like motif in wild-type and mutant CdtC. The numbers indicate the positions of the amino acid residues. The putative CRAC-like motifs are in boxes. The amino acids in boldface indicate the residues targeted for substitution. (B) Structural model of cholesterol was in complex with putative CRAC of CdtC^wt. The cholesterol was shown in stick and colored in blue. The number of amino acids shown in CdtC^wt directly interacted with the cholesterol-binding sites. Oxygen atom localized in cholesterol and amino acids were shown in red. (C) Cholesterol showed hydrophobic interactions with L77, P78, F79, G80, Y81, and V82 (boldface lines in green), and formed a hydrogen bond with V82 (dash line in green). Modeling simulation was performed using PyMol, as described in the Materials and Methods.