Related Experiment Video
Updated: Jul 11, 2026

Computational Prediction of Amino Acid Preferences of Potentially Multispecific Peptide-Binding Domains Involved in Protein-Protein Interactions
Published on: January 26, 2024
Optimization of the gbeta1 domain by computational design and by in vitro evolution: structural and energetic basis
Michael Wunderlich1, Klaas E A Max, Yvette Roske
1Laboratorium für Biochemie und Bayreuther Zentrum für Molekulare Biowissenschaften, Universität Bayreuth, D-95440 Bayreuth, Germany.
Abstract:
Computational design and in vitro evolution are major strategies for stabilizing proteins. For the four critical positions 16, 18, 25, and 29 of the B domain of the streptococcal protein G (Gbeta1), they identified the same optimal residues at positions 16 and 25, but not at 18 and 29. Here we analyzed the energetic contributions of the residues from these two approaches by single and double mutant analyses and determined crystal structures for a variant from the calculation (I16/L18/E25/K29) and from the selection (I16/I18/E25/F29). The structural analysis explains the observed differences in stabilization. Residues 16, 18, and 29 line an invagination, which results from a packing defect between the helix and the beta-sheet of Gbeta1. In all stabilized variants, residues with larger side-chains occur at these positions and packing is improved. In the selected variant, packing is better optimized than in the computed variant. Such differences in side-chain packing strongly affect stability but are difficult to evaluate by computation.
Related Concept Videos
Conserved Binding Sites
Binding sites are often located in large pockets, and if their location on a protein’s surface is unknown, it can be predicted using various approaches. The energetic method computationally analyses the...
Conservation of Protein Domains Over Different Proteins
A limited set of protein domains often duplicate and recombine during evolution. These domains can be organized in different combinations to form...
Gene Families
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...

