Stabilizing and Destabilizing Effects of Phenylalanine → F5-Phenylalanine Mutations on the Folding of a Small Protein

摘要: We report a systematic evaluation of phenylalanine-to-pentafluorophenylalanine (Phe --> F5-Phe) mutants for the 35-residue chicken villin headpiece subdomain (c-VHP), hydrophobic core which features cluster three Phe side chains (residues 6, 10, and 17). F5-Phe mutations are interesting because aryl-perfluoroaryl interactions optimal geometry intrinsically more favorable than aryl-aryl perfluoroaryl units analogous aryl units. One mutant, Phe-10 F5-Phe, provides enhanced tertiary structural stability relative to native sequence. The other six analyzed caused decrease in stability.