2019/07/15 by Qingping Xu, Matthew Biancalana, Joanna C. Grant +8 · 1 citation
Biochemistry, Genetics and Molecular Biology · Chemistry · Materials Science · #Beta sheet #Biochemistry #Biology #Biophysics #Chemistry #Crystallography #Enzyme Structure and Function #Folding (DSP implementation) #Glycosylation and Glycoproteins Research #Hydrogen bond #Molecule #Protein Structure and Dynamics #Protein folding #Protein structure
paper · pdf · doi:10.1002/pro.3683
openalex publication_date 2019/07/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/06
Free-standing single-layer β-sheets are extremely rare in naturally occurring proteins, even though β-sheet motifs are ubiquitous. Here we report the crystal structures of three homologous, single-layer, anti-parallel β-sheet proteins, comprised of three or four twisted β-hairpin repeats. The structures reveal that, in addition to the hydrogen bond network characteristic of β-sheets, additional hydrophobic interactions mediated by small clusters of residues adjacent to the turns likely play a significant role in the structural stability and compensate for the lack of a compact hydrophobic core. These structures enabled identification of a family of secreted proteins that are broadly distributed in bacteria from the human gut microbiome and are putatively involved in the metabolism of complex carbohydrates. A conserved surface patch, rich in solvent-exposed tyrosine residues, was identified on the concave surface of the β-sheet. These new modular single-layer β-sheet proteins may serve as a new model system for studying folding and design of β-rich proteins.