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Updated: Jul 15, 2026
09:16
In Vitro Directed Evolution of a Restriction Endonuclease with More Stringent Specificity
Published on: March 25, 2020
Sequence comparison and environmental adaptation of a bacterial endonuclease
Bjørn Altermark1, Steinar Thorvaldsen, Elin Moe
1Norwegian Structural Biology Centre, Faculty of Science, University of Tromsø, N-9037 Tromsø, Norway.
Computational Biology and Chemistry
|May 15, 2007
Summary
This study reveals how bacterial endonuclease I adapts to different temperatures and salt concentrations. Cold adaptation involves increased surface charge and hydrophobicity, while salt adaptation shows the opposite trend.
Area of Science:
- Biochemistry
- Molecular Biology
- Enzymology
Background:
- Endonuclease I is a periplasmic/extracellular bacterial enzyme.
- Understanding enzyme adaptation to environmental factors like temperature and salinity is crucial.
Purpose of the Study:
- To identify amino acid sequence features responsible for temperature and salt adaptation in endonuclease I.
- To investigate environmental adaptation of enzymes using novel bioinformatic methods.
Main Methods:
- Statistical analysis of amino acid sequence properties of endonuclease I from various habitats and temperature groups.
- Sequencing of ten new endonuclease I genes.
- Application of property-dependent statistical analysis of alignments.
Main Results:
- Cold adaptation correlates with increased surface isoelectric point and hydrophobicity.
- Salt adaptation correlates with decreased surface isoelectric point and hydrophobicity.
- Redistribution of charge and hydrophobicity are key signatures for adaptation.
Conclusions:
- General trends of enzyme adaptation can be elucidated from amino acid sequences.
- This study presents a novel scale of stratified B-factors derived from the Protein Data Bank.
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