Evolution of structure and function of Class I peroxidases

Area of Science:

• Biochemistry
• Molecular Evolution
• Phylogenetics

Background:

• The heme peroxidase-catalase superfamily, particularly Class I, comprises over 940 known sequences across prokaryotic and eukaryotic genomes.
• Understanding the evolutionary history and relationships within this superfamily is crucial for deciphering enzyme function and origin.

Purpose of the Study:

• To analyze the phylogenetics of Class I heme peroxidases.
• To reconstruct the evolutionary tree and identify key trends in molecular evolution.
• To investigate the potential transfer of peroxidase genes from prokaryotes to eukaryotes.

Main Methods:

• Phylogenetic analysis of 193 Class I peroxidases.
• Inclusion of 6 selected Class II peroxidase representatives for comparative analysis.
• Reconstruction of a robust phylogenetic tree.

Main Results:

• The reconstructed tree illustrates major trends in molecular evolution for Class I peroxidases.
• Evidence suggests the ancestral peroxidase gene transfer from prokaryotic to eukaryotic genomes.
• Two novel, distinct clades of hybrid-type peroxidases (Type A and Type B) were identified, potentially bridging known peroxidase families.

Conclusions:

• The study provides insights into the origin and evolution of catalytic promiscuity and specificity in peroxidases.
• The identified hybrid peroxidases may represent evolutionary links between catalase-peroxidases, cytochrome c peroxidases, and Class II peroxidases.
• The findings offer a foundation for future functional analyses and de novo design of Class I enzymes.