Peptidome: Chaos or Inevitability

Area of Science:

• Biochemistry
• Molecular Biology
• Proteomics

Background:

• Peptidomes, the complete set of peptides in an organism, are largely uncharacterized.
• Thousands of naturally occurring peptides exist in various organisms, with many possessing unknown functions.
• A growing body of evidence suggests the presence of numerous undiscovered bioactive peptides within these peptidomes.

Purpose of the Study:

• To provide a comprehensive overview of peptidome generation mechanisms and properties.
• To propose a classification of peptides based on their origin.
• To compare and discuss peptidome composition across different species.

Main Methods:

• Literature review of peptidome generation and properties.
• Classification of peptides into three main groups: degradome, smORFome, and precursor-derived peptides.
• Comparison of mass spectrometry data from human cells, plants, yeast, and bacteria.

Main Results:

• Peptidomes are generated through various mechanisms and exhibit diverse properties.
• Three major peptide groups are proposed: functional protein "degradome", small open reading frame (smORF)-encoded peptides (smORFome), and specific precursor-derived peptides.
• Mass spectrometry analysis reveals variations in peptidome composition across different organisms.

Conclusions:

• The study categorizes and compares peptidomes across diverse organisms.
• The "degradome" plays a role in defense signaling.
• Further research into the vast, poorly characterized peptidomes is warranted to discover novel bioactive peptides.