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Updated: Jan 25, 2026

Molecular Evolution of the Tre Recombinase

Molecular Evolution of the Tre Recombinase

Published on: May 29, 2008

Molecular Evolution in Large Steps-Codon Substitutions under Positive Selection.

Qingjian Chen¹, Ziwen He¹, Ao Lan¹

¹State Key Laboratory of Biocontrol, School of Life Sciences, Sun Yat-Sen University, Guangzhou, China.

Molecular Biology and Evolution

|May 12, 2019

Summary

This summary is machine-generated.

Molecular evolution often involves large functional steps, not just small ones. Positive selection drives significant amino acid changes, suggesting a common biochemical basis for adaptation across species.

Keywords:

Fisher’s geometric model codon evolution natural selection positive selection

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Last Updated: Jan 25, 2026

Molecular Evolution of the Tre Recombinase

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Published on: May 29, 2008

Identifying Amino Acid Overproducers Using Rare-Codon-Rich Markers

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Mutagenesis and Functional Selection Protocols for Directed Evolution of Proteins in E. coli

Mutagenesis and Functional Selection Protocols for Directed Evolution of Proteins in E. coli

Published on: March 16, 2011

Area of Science:

Evolutionary biology
Molecular evolution
Biochemistry

Background:

Molecular evolution is traditionally viewed as a gradual process.
The physico-chemical properties of amino acid substitutions determine the 'step size' in molecular evolution.

Purpose of the Study:

To investigate the relationship between amino acid substitution rates, physico-chemical distances, and the influence of positive and negative selection.
To determine if positive selection favors larger or smaller functional steps in molecular evolution.

Main Methods:

Utilized the McDonald and Kreitman test to differentiate between positive and negative selection.
Analyzed amino acid substitution rates against physico-chemical distances between amino acid pairs.
Examined substitution patterns across Drosophila and Hominoids.

Main Results:

Amino acid substitution rates negatively correlate with physico-chemical distance under weak positive selection.
Negative selection acts more strongly on substitutions with larger chemical property changes.
Positive selection, however, favors large functional leaps in amino acid properties for a subset of substitutions, with some shared across taxa.

Conclusions:

Adaptive molecular evolution may involve significant functional jumps, challenging the notion of purely incremental change.
The findings suggest a potential common biochemical basis for adaptation across diverse taxa.
Future molecular models should incorporate both positive and negative selection dynamics to better identify adaptive signals.