Origins of peptidases

Area of Science:

• Biochemistry
• Evolutionary Biology
• Genomics

Background:

• Peptidases are crucial enzymes involved in protein metabolism across all domains of life.
• Understanding peptidase origins provides insights into early cellular evolution and the Last Universal Common Ancestor (LUCA).

Purpose of the Study:

• To analyze the distribution of 271 peptidase families across all known phyla.
• To determine the ancestral origin of each peptidase family within the tree of life.
• To compare peptidase evolution with current hypotheses on organismal evolution.

Main Methods:

• Bioinformatic analysis of peptidase homologues across diverse organisms.
• Phylogenetic analysis to trace the evolutionary history of peptidase families.
• Comparative genomics to identify conserved and lineage-specific peptidases.

Main Results:

• No single peptidase family is found in all organisms; even essential peptidases like signal peptidase are absent in some clades.
• 33 peptidase families are conserved across Archaea, Bacteria, and Eukaryotes, suggesting LUCA origin.
• Evidence indicates that diverse catalytic types and structures of peptidases predate LUCA.
• Other families originated in the ancestors of viruses, archaea, bacteria, fungi, plants, and animals, or specific phyla.

Conclusions:

• Peptidase evolution is complex, with origins spanning from before LUCA to specific lineages.
• The distribution patterns of peptidases offer a unique perspective on the early evolution of life and the diversification of organisms.