@article{MTMT:2868602, title = {Induced Folding of Protein-Sized Foldameric β-Sandwich Models with Core β-Amino Acid Residues}, url = {https://m2.mtmt.hu/api/publication/2868602}, author = {Olajos, Gábor and Hetényi, Anasztázia and Wéber, Edit and Németh, Lukács and Szakonyi, Zsolt and Fülöp, Ferenc and Martinek, Tamás}, doi = {10.1002/chem.201405581}, journal-iso = {CHEM-EUR J}, journal = {CHEMISTRY-A EUROPEAN JOURNAL}, volume = {21}, unique-id = {2868602}, issn = {0947-6539}, abstract = {The mimicry of protein-sized β-sheet structures with unnatural peptidic sequences (foldamers) is a considerable challenge. In this work, the de novo designed betabellin-14 β-sheet has been used as a template, and α→β residue mutations were carried out in the hydrophobic core (positions 12 and 19). β-Residues with diverse structural properties were utilized: Homologous β3-amino acids, (1R,2S)-2-aminocyclopentanecarboxylic acid (ACPC), (1R,2S)-2-aminocyclohexanecarboxylic acid (ACHC), (1R,2S)-2-aminocyclohex-3-enecarboxylic acid (ACEC), and (1S,2S,3R,5S)-2-amino-6,6-dimethylbicyclo[3.1.1]heptane-3-carboxylic acid (ABHC). Six α/β-peptidic chains were constructed in both monomeric and disulfide-linked dimeric forms. Structural studies based on circular dichroism spectroscopy, the analysis of NMR chemical shifts, and molecular dynamics simulations revealed that dimerization induced β-sheet formation in the 64-residue foldameric systems. Core replacement with (1R,2S)-ACHC was found to be unique among the β-amino acid building blocks studied because it was simultaneously able to maintain the interstrand hydrogen-bonding network and to fit sterically into the hydrophobic interior of the β-sandwich. The novel β-sandwich model containing 25% unnatural building blocks afforded protein-like thermal denaturation behavior. Dissolving sandwiches: A water-soluble β-sandwich has been constructed by using cyclic β-amino acids in the hydrophobic core (see figure). The structural stability is highly dependent on the side-chain, and the destructuring effects of the β-residues could be minimized by using (1R,2S)-2-aminocyclohexanecarboxylic acid. The β-sandwich displays protein-like thermal denaturation behavior.}, keywords = {PROTEINS; STABILITY; Protein Folding; Chemical bonds; amino acids; PEPTIDOMIMETICS; DICHROISM; molecular dynamics; chemical analysis; DYES; Hydrophobicity; Hydrogen bonds; molecular dynamics simulations; CHAINS; circular dichroism spectroscopy; Structural stabilities; Protein Engineering; Thermal denaturations; Hydrogen bonding network; NMR chemical shifts; PROTEIN STRUCTURES}, year = {2015}, eissn = {1521-3765}, pages = {6173-6180}, orcid-numbers = {Hetényi, Anasztázia/0000-0001-8080-6992; Wéber, Edit/0000-0002-5904-0619; Szakonyi, Zsolt/0000-0003-2432-8409; Fülöp, Ferenc/0000-0003-1066-5287; Martinek, Tamás/0000-0003-3168-8066} }