Antimicrobial Peptide AP00144






Magainin 2 (Magainin II, PGS; Hebrew "shield"; UCLL1; frog, amphibians, animals. BBMm; BBL; Derivatives: MSI-78, pexiganan acetate, or cytolex, loxilex; clinical trials; MSI-594; MSI-99.



skin; Stomach, African clawed frog, Xenopus laevis, Africa








Net charge:



Hydrophobic residue%:



Boman Index:

0.41 kcal/mol


3D Structure:






SwissProt ID:

PDB ID: 2MAG   Go to PDB



Anti-Gram+ & Gram-, Antiviral, Antifungal, candidacidal, Antiparasitic, Insecticidal, Spermicidal, anti-sepsis, Antimalarial, Wound healing, Anticancer


Additional info:

Discovery: The same peptide sequence was also reproted by Giovannini MG et al in 1987 as PGS without antibacterial data.

Activity description: Active against E. coli D31 (MIC 5 ug/ml), K. pneumoniae, P. putida, S. epidermidis (MIC 10 ug/ml), C. freundii (MIC 30 ug/ml), E. cloacae, E. coli, S. aureus (MIC 50 ug/ml), C. albicans (MIC 80 ug/ml), P. aeruginosa, and S. marcescens (MIC 100 ug/ml). Also S. pyogenes, and S. cerevisiae. Also active against P. falciparum, protozoan P. caudatum, A. castellani and T. pyriformis. Also active against B. dendrobatidis (Table 1, Rollins-Smith, BBA 2009; 1788:1593-1599). Magainin II shows a synergistic effect with cecropin A (J Antimicrob Chemother. 2008; 62:1332-8). MOA: it kills bacteria by targeting membranes and forming a pore (forms D=L). It also inhibits Herpes Simplex Virus type 1 (HSV-1) and HSV-2 (PubMed2004). Magainin II only showed a weak activity against channel catfish virus (ref) as well as P388 leukemia, S180 ascites, and a spontaneous ovarian tumor (Baker et al., 1993). It is also insecticidal (EC50 123 pmol/mg fly).

Structure: Alpha helix: residues 4-21 in TFE, SDS, DPC (for the ref., go to PDB website below). You can rotate, zoom, and view the 3D structure here in the PDB .

Derivative 1: MSI-78 (provided by Ed Ezell) (sequence GIGKFLKKAKKFGKAFVKILKK-NH2) is active against bacteria such as E. coli, S. aureus, and P. aeruginosa and fungi. Pexiganan has wound healing activity. It was subjecte to clinical trials but was not approved by FDA due to the cytotoxicity issue. Derivative 2: MSI-594 (provided by Ed Ezell) (sequence GIGKFLKKAKKGIGAVLKVLTTGL-NH2) is engineered based on magainin and melittin. Derivative 3: NSI-99: transgenic plants: expression of a magainin analog (MSI-99, sequence GIGKFLKSAKKFGKAFVKIKNS-NH2, 22mer, more basic) in tomato and banana reduced bacterial speck disease (Planta. 2003 Feb;216(4):587-96).

Surface immobilization: Magainin has also been covalently immobilized 1995 S L Haynie et al. to a water insoluble resin. Edited 4/2017; updated 9/2017; 8/2019.



Magainins, a class of antimicrobial peptides from Xenopus skin: isolation, characterization of two active forms, and partial cDNA sequence of a precursor.



Zasloff M.1987



Proc Natl Acad Sci U S A. 1987 Aug;84(15):5449-53. PubMed.


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