부산대학교 도서관

Protein structural motifs such as helical assemblies and α⧸β barrels combine secondary structure elements with various types of interactions. Helix–helix interfaces of assemblies – Ankyrin, ARM/HEAT, PUM, LRR, and TPR repeats – exhibit unique amino acid composition and patterns of interactions that correlate with curvature of solenoids, surface geometry and mutual orientation of the helical edges. Inner rows of ankyrin, ARM/HEAT, and PUM-HD repeats utilize edges ( i −1, i ) and ( i +1, i +2) for the interaction of the given α-helix with preceding and following helices correspondingly, whereas outer rows of these proteins and LRR repeats invert this pattern and utilize edges ( i −1, i ) and ( i −3, i −2). Arrangement of contacts observed in protein ligands that bind helical assemblies has to mimic the assembly pattern to provide the same curvature as a determinant of binding specificity. These characteristics are important for understanding fold recognition, specificity of protein–protein interactions, and design of new drugs and materials. [ABSTRACT FROM AUTHOR]