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Updated: May 20, 2026
11:36
A Protocol for Functional Assessment of Whole-Protein Saturation Mutagenesis Libraries Utilizing High-Throughput Sequencing
Published on: July 3, 2016
Sequence-function-stability relationships in proteins from datasets of functionally annotated variants: the case of
Luciano A Abriata1, Merijn L M Salverda, Pablo E Tomatis
1Instituto de Biología Molecular y Celular de Rosario, Rosario, Argentina. luciano.abriata@epfl.ch
FEBS Letters
|August 2, 2012
Summary
TEM lactamase evolution shows loops accumulate mutations for complex functions. Stability-restoring substitutions aid this, but may be site-specific, not global.
Area of Science:
- Enzymology
- Protein Engineering
- Molecular Evolution
Background:
- TEM lactamases are crucial enzymes conferring antibiotic resistance.
- Understanding their evolution is key to combating antimicrobial resistance.
- Previous studies have highlighted mutation accumulation but lacked detailed functional analysis.
Purpose of the Study:
- To analyze a dataset of TEM lactamase variants to understand evolutionary trends.
- To investigate the role of protein loops and specific mutations in functional diversification.
- To explore the relationship between functional complexity, stability, and mutation patterns.
Main Methods:
- Compilation and analysis of a curated dataset of TEM lactamase variants.
- Identification of key evolvable regions and mutation patterns.
- Correlation of mutations with substrate specificity and inhibition profiles.
- Investigation of function-stability trade-offs and substitution networks.
Main Results:
- Protein loops are identified as the primary regions for TEM lactamase evolution.
- Accumulation of mutations in loops drives the development of complex enzymatic functions.
- Functional promiscuity arises from mutations found in both simple and evolved variants.
- Stability-restoring substitutions are necessary for complex functions but appear site-specific.
Conclusions:
- TEM lactamase evolution is characterized by loop-driven functional diversification.
- The study provides insights into the mechanisms of enzyme adaptation and resistance.
- The findings can inform the development of predictive models for enzyme functional changes.
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