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Updated: Jun 26, 2026
08:06
The Use of a β-lactamase-based Conductimetric Biosensor Assay to Detect Biomolecular Interactions
Published on: February 1, 2018
Re-engineering a beta-lactamase using prototype peptides from a library of local structural motifs
Valeria A Risso1, María E Primo, Mario R Ermácora
1Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Bernal, Buenos Aires, Argentina.
Protein Science : a Publication of the Protein Society
|January 24, 2009
Summary
Researchers engineered bacterial beta-lactamase by replacing alpha helices with unrelated structures. Remarkably, variants retained native-like folds and enzymatic activity, challenging protein folding and evolution theories.
Area of Science:
- Protein engineering
- Molecular biology
- Biochemistry
Background:
- Bacillus licheniformis exo-small beta-lactamase (ESBL) possesses a complex structure.
- Protein structure is crucial for function and stability.
Purpose of the Study:
- To investigate the impact of replacing native alpha helices with artificial amphipathic helices on ESBL structure and function.
- To explore the limits of protein folding and evolution by creating non-homologous protein variants.
Main Methods:
- Engineering of B. licheniformis ESBL by substituting native alpha helices with prototype amphipathic helices.
- In vitro and in vivo assays to assess the folding, stability, and enzymatic activity of engineered variants.
- Structural and functional characterization of the triple-substituted variant.
Main Results:
- Engineered ESBL variants, including a triple-substituted mutant, successfully folded into native-like structures.
- All variants exhibited in vitro and in vivo enzymatic activity, demonstrating functional retention despite sequence divergence.
- The triple-substituted variant displayed characteristics of a primitive protein, including oligomerization and low stability, while preserving the overall fold.
Conclusions:
- Protein fold can be maintained even with significant sequence and structural substitutions, suggesting a degree of modularity in protein architecture.
- The study provides evidence supporting theories of protein folding and evolution, particularly concerning the potential for creating novel protein structures from unrelated elements.
- Engineered proteins can mimic non-homologous recombinants, expanding the understanding of protein sequence-structure-function relationships.
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