Engineering and Characterization of Thermostable Xylanases

Thermostable xylanases, enzymes that catalyse the breakdown of xylan into xylooligosaccharides and xylose at elevated temperatures, have become indispensable in industries ranging from pulp and paper to biofuel production and animal feed. Engineering efforts focus on enhancing thermal resistance without compromising catalytic efficiency, using approaches such as rational design, directed evolution, disulphide‐bridge introduction, surface entropy reduction and N- or C-terminal truncation. Structural analyses via X-ray crystallography and molecular dynamics simulations provide atomistic insight into stability determinants, guiding targeted modifications. Characterization assays—thermal denaturation profiles, kinetic measurements on natural and pretreated substrates, and assessments under harsh chemical or saline conditions—ensure that engineered variants meet industrial requirements. Such advances facilitate sustainable biomass conversion, prebiotic xylooligosaccharide manufacture and robust enzyme deployment in high-temperature processes worldwide.

Research from Nature Portfolio

One study improved the thermostability of an acidic xylanase from Aspergillus sulphureus by introducing tailored disulphide bridges and proline substitutions. The best mutant exhibited a 22-fold increase in half-life at 60 °C and retained high activity upon scale-up in a 10 L fermentor. A second report described rational N-terminal engineering of a GH11 xylanase from Talaromyces leycettanus. Single- and multi-site variants achieved melting temperature gains of up to ~8 °C, while molecular dynamics simulations revealed new hydrophobic and hydrogen-bond networks that rigidify surface loops and substrate-binding regions. These foundational works demonstrate how structure-guided modification can yield xylanases with both enhanced thermal resilience and retained catalytic throughput.

Engineering and Characterization of Thermostable Xylanases publication trend

The graph below shows the total number of articles in engineering and characterization of thermostable xylanases across all publications each year (not limited to Nature Index journals).

Technical terms

Xylan: A hemicellulosic polysaccharide composed of β-1,4-linked xylose units in plant cell walls.

Xylanase: An enzyme that hydrolyses xylan into xylooligosaccharides or xylose.

Thermostability: Capacity of a protein to retain structure and catalytic activity at elevated temperatures.

Glycoside hydrolase family 11 (GH11): A class of xylanases with a β-jelly-roll fold and high substrate specificity.

Directed evolution: Iterative laboratory process of mutagenesis and selection to enhance protein traits.

Rational design: Targeted introduction of mutations based on structural or sequence insights.

Site-directed mutagenesis: Technique for precise substitution of amino acids in a protein.

Molecular dynamics simulation: Computational modelling of atomic motions to assess protein stability.

References

1. Improved thermostability of an acidic xylanase from Aspergillus sulphureus by combined disulphide bridge introduction and proline residue substitution. Scientific Reports (2017).
2. Thermostability improvement of a Talaromyces leycettanus xylanase by rational protein engineering. Scientific Reports (2017).
3. Three Molecular Modification Strategies to Improve the Thermostability of Xylanase XynA from Streptomyces rameus L2001. Foods (2023).
4. Molecular Identification and Engineering a Salt-Tolerant GH11 Xylanase for Efficient Xylooligosaccharides Production. Biomolecules (2024).
5. Improvement of thermostability and catalytic efficiency of xylanase from Myceliophthora thermophilar by N-terminal and C-terminal truncation. Frontiers in Microbiology (2024).