Fungal Laccases: Fundamentals, Engineering and Classification Update

Area of Science:

• Biochemistry and Biotechnology
• Enzymology
• Genomics

Background:

• Multicopper oxidases (MCOs) share conserved catalytic mechanisms and structures.
• Fungal laccases are key MCOs with broad substrate specificity for aromatic compounds and lignin, crucial for industrial applications.
• Protein engineering and directed evolution can enhance laccase performance for specific industrial processes.

Purpose of the Study:

• To review the structure, catalytic activity, and oxidative mechanisms of fungal laccases.
• To discuss the enhancement of fungal laccases' biotechnological potential via protein engineering.
• To present recent findings on newly identified MCOs with laccase-like activity.

Main Methods:

• Comparative genomic analysis of 52 basidiomycete fungi.
• Phylogenetic analysis of MCOs to revise classification.
• Review of existing literature on fungal laccase structure, function, and engineering.

Main Results:

• MCO classification was revised based on phylogeny, revealing three novel groups of laccase-like enzymes.
• The study highlights challenges in classifying laccases due to low sequence homology and automatic annotation errors.
• Identified MCOs with laccase-like activity expand the known diversity of these enzymes.

Conclusions:

• Revised classification and identification of novel laccase-like enzymes improve understanding and potential applications.
• Protein engineering offers significant opportunities to enhance the industrial utility of fungal laccases.
• Accurate classification and characterization are essential for leveraging MCOs in biotechnology.