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Peptide Modifications intermediate

Peptide Phosphorylation Sites

Guide to phosphorylation of serine, threonine, and tyrosine residues in peptide signaling.

By Encyclopeptide Editorial | 1 min read
phosphorylation kinase signaling modification

Overview

Phosphorylation is the most common post-translational modification, regulating protein activity through kinase-mediated phosphate addition.

Residue Specificity

  • Serine: Most frequent (~85% of phosphorylation)
  • Threonine: Second most common (~10%)
  • Tyrosine: Less frequent but critical in signaling (~5%)

Biological Significance

Phosphorylation acts as a molecular switch controlling cell cycle, signal transduction, metabolism, and gene expression. Dysregulation drives cancer and metabolic diseases.

References

  • Source: ENCP Peptide Database
  • Category: Peptide Modifications

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