A disulfide-stabilized beta-hairpin AMP with rapid, broad-spectrum microbicidal activity in research models.
Also known as: PG-1 · protegrin
Part of the Foundational & therapeutic peptides cluster
Overview
Protegrin-1 (PG-1) is an 18-residue arginine-rich antimicrobial peptide from porcine leukocytes. Two disulfide bonds lock it into an antiparallel beta-hairpin that forms membrane pores, giving rapid broad-spectrum activity in research. Its high activity against mammalian cells has limited systemic development; it remains a research peptide.
Source & context
Biological / chemical source: Porcine leukocytes (cathelicidin family)
Primary research or clinical context: Antimicrobial-peptide research (not an approved drug)
Beta-hairpin architecture
Unlike helical AMPs, protegrin-1 folds into a rigid beta-hairpin held by two cysteine disulfide bridges, with six cationic arginines. This scaffold enables fast membrane pore formation and is a favored template in AMP structure-activity research.
Research context and limits
In vitro, PG-1 is rapidly bactericidal against MRSA, Pseudomonas and other pathogens at low concentrations. However, notable hemolytic activity toward mammalian cells has driven design of safer analogs. This page is educational and describes research findings, not therapy.
Sequence
One-letter sequence commonly cited for Protegrin-1 (educational; isoforms and modifications may differ):
RGGRLCYCRRRFCVCVGR
Residues plotted ~100° apart around an α-helix — clustering of one color reveals an amphipathic face.
FAQ about Protegrin-1
What is Protegrin-1?+
Protegrin-1 (PG-1) is an 18-residue arginine-rich antimicrobial peptide from porcine leukocytes. Two disulfide bonds lock it into an antiparallel beta-hairpin that forms membrane pores, giving rapid broad-spectrum activity in research. Its high activity against mammalian cells has limited systemic development; it remains a research peptide.
Is Protegrin-1 an approved medicine?+
Protegrin-1 is discussed here as a research / educational topic. Antimicrobial-peptide research (not an approved drug). This is not medical advice.
What is the typical length of Protegrin-1?+
Protegrin-1 is commonly described as approximately 18 amino acids (Antimicrobial peptide).