A feruloyl esterase derived from a leachate metagenome library

Area of Science:

• Biochemistry
• Enzymology
• Molecular Biology

Background:

• Feruloyl esterases (FAEs) are crucial enzymes for breaking down ferulated polysaccharides.
• Metagenomic libraries offer a promising source for discovering novel enzymes with industrial applications.

Purpose of the Study:

• To clone, express, and characterize a novel feruloyl esterase gene (fae6) from a leachate metagenomic library.
• To evaluate the biochemical properties and potential applications of the Fae6 enzyme.

Main Methods:

• Gene cloning and nucleotide sequencing of the fae6 gene.
• Over-expression of the recombinant Fae6 protein in E. coli and subsequent purification.
• Biochemical characterization including kinetic (K(M)) and thermostability analysis.

Main Results:

• The fae6 gene encodes a 515 amino acid polypeptide with a conserved catalytic serine motif.
• Recombinant Fae6 was successfully purified with 8.4-fold enrichment.
• Fae6 exhibited high affinity for methyl sinapate, methyl ferulate, and ethyl ferulate.
• The enzyme was thermolabile, with a half-life of less than 30 minutes at 50°C.

Conclusions:

• The Fae6 enzyme possesses characteristics suitable for hydrolyzing ferulated polysaccharides.
• Its high affinity for specific substrates suggests potential applications in biorefinery processes.
• Further research may optimize Fae6 for industrial use, despite its thermolability.