β-sheet structures contain parallel and antiparallel strands with an extended backbone, that permits hydrogen bonding between the backbone amides and carbonyls. The arrangement of C and N-termini of the beta strands (on the same side-parallel and alternate sides-antiparallel) has an important impact on the H-bonding, side chains, and orientations in the structure. Interactions among β-sheets occur widely in protein quaternary structure, protein–protein interaction, and protein aggregation and are central in Alzheimer’s and other amyloid-related diseases. Common themes in the supramolecular interactions of β-sheets are identified and richly illustrated though examples from proteins, amyloids, and chemical model systems. β-Sheets interact through edge-to-edge hydrogen bonding to form extended layers and through face-to-face hydrophobic or van der Waals interactions to form layered sandwich-like structures. Side chains from adjacent layers can fit together through simple hydrophobic contacts or can participate in complementary interdigitation or knob–hole interactions. The layers can be aligned, offset, or rotated. The right-handed twist of β-sheets provides additional opportunities for stabilization of edge-to-edge contacts and rotated layered structures. Here you can see the crystal structure of a beta-sheet formed heterodimer (PDB code: 6WMK)

#molecularart ... #betastrand ... #betasheet ... #dimer ... #hydrogenbond ... #xray

Structure rendered with @proteinimaging and depicted with @corelphotopaint