<p><i>(Top)</i> The interactions at the top of the V-shaped dimer are maintained by a hydrophobic core of the two symmetrical Trp247 surrounded by two polar interaction patches. The first polar patch includes Arg238-Glu282 salt bridge with additional polar interactions to Asp245 side chain and the backbone carbonyl of Val242. The second patch includes a double Arg238-Glu282-Arg240 salt bridge. <i>(Bottom)</i> The interactions at the bottom of the V-shaped dimer include two interaction patches, the first is stabilized by an Arg260-Glu265 salt bridge with additional polar interactions to the side chains of Glu268 and His264. The second, lower, interaction patch is stabilized by a single Arg260-Glu268 salt bridge.</p
