| Field | Specification |
|---|---|
| Alternative names | MSI 78 |
| CAS no. | |
| Applications | |
| Source | Animal — the skin of the African clawed frog |
| Molecular weight | |
| Molecular formula | C122H210N32O22.xC2H4O2 |
| Purity | |
| Form | Solid |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
Pexiganan acetate, also known as MSI 78, is an orally active antimicrobial peptide with broad-spectrum bactericidal activity. Pexiganan TFA disrupts bacterial cell membranes and induces peptidoglycan damage and cell lysis, and the compound can be used for research on bacterial infection[1][2][3][4]. It is supplied as a white to off-white solid (C122H210N32O22.xC2H4O2, MW 2477.17, free base) at 99.31% purity.
Physical & Chemical Properties
| CAS Number | 172820-23-4 |
|---|---|
| Molecular Formula | C122H210N32O22.xC2H4O2 |
| Molecular Weight | 2477.17 (free base) g/mol |
| Purity | 99.31% |
| Appearance | Solid |
| Color | White to off-white |
| Structure Classification | Others |
| Sequence | Gly-Ile-Gly-Lys-Phe-Leu-Lys-Lys-Ala-Lys-Lys-Phe-Gly-Lys-Ala-Phe-Val-Lys-Ile-Leu-Lys-Lys-NH2 |
| Sequence (one-letter) | GIGKFLKKAKKFGKAFVKILKK-NH2 |
| Signaling Pathway | Anti-infection |
| Initial Source | Animal — the skin of the African clawed frog |
| Storage | Sealed storage, away from moisture. Powder: -80°C, 2 years; -20°C, 1 year. In solvent: -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture). |
| Shipping | Room temperature in continental US; may vary elsewhere. |
Literature Cited
Sources cited in this description and in the In Vitro & In Vivo Data tab. Peer-reviewed publications that used this product are listed under References.
Safety
For Research Use Only. Not for use in diagnostic or therapeutic procedures, and not for human or veterinary use. Handle in accordance with the Safety Data Sheet and your institution's chemical hygiene plan.
In Vitro
Bactericidal activity of Pexiganan (1-256 μg/mL; 24 h) acetate is comparable for planktonic Staphylococcus aureus Z25.2, Pseudomonas aeruginosa Z25.1, and cultures that combine both species[1]. Biofilms of Staphylococcus aureus Z25.2 are inhibited and eradicated more effectively by Pexiganan (1-256 μg/mL; 24 h) acetate than are Pseudomonas aeruginosa Z25.1 or dual-species biofilms[1]. Purified bovine type I collagen is bound by Pexiganan (7-35 μM) acetate, with a dissociation constant of 34.01 μM[3]. Growth of Pseudomonas aeruginosa and Staphylococcus aureus is inhibited by Pexiganan (5-80 μg/mL; overnight) acetate[3]. Over 60 min, viable counts of Pseudomonas aeruginosa (ATCC27853) and Staphylococcus aureus (ATCC29213) fall rapidly with Pexiganan (40 μg/mL; 0-60 min) acetate, and P. aeruginosa is completely eliminated by 60 min[3]. No cytotoxicity toward rat fibroblast cells is seen with Pexiganan (10-50 μg/mL) acetate in in vitro MTT assays[3].
In Vivo
In mice with septic shock induced by E. coli O111:B4 LPS, TNF-α levels are reduced by Pexiganan (1 mg/kg; i.p.; single dose) acetate[4]. Lethality and intra-abdominal bacterial counts are reduced by Pexiganan (1 mg/kg; i.p.; single dose) acetate in male Wistar rats with E. coli-induced septic shock[4]. In male Wistar rats with septic shock induced by cecal ligation and puncture, Pexiganan (1 mg/kg; i.p.; single dose) acetate lowers lethality and intra-abdominal bacterial counts[4]. No detectable adverse effects or physiological changes occur in healthy male Wistar rats given Pexiganan (1 mg/kg; i.p.; single dose) acetate, which is well-tolerated[4].
| Animal Model | Wistar rats (adult male, 200-300 g, E. coli O111:B4 LPS-induced septic shock)[4] |
|---|---|
| Dosage | 1 mg/kg |
| Administration | i.p.; single dose |
| Result | Reduced plasma endotoxin levels to ≤0.015 EU/mL. Reduced plasma TNF-α levels to 0.26 ng/mL. |
| Animal Model | Wistar rats (adult male, 200-300 g, E. coli-induced septic shock)[4] |
|---|---|
| Dosage | 1 mg/kg |
| Administration | i.p.; single dose |
| Result | Resulted in 32.3% lethality, 5/15 positive blood cultures, and intra-abdominal bacterial counts of 6.0 × 103 CFU/mL. |
| Animal Model | Wistar rats (adult male, 200-300 g, cecal ligation and puncture-induced septic shock)[4] |
|---|---|
| Dosage | 1 mg/kg |
| Administration | i.p.; single dose |
| Result | When administered immediately after surgery, resulted in 32.3% lethality, 5/15 positive blood cultures, and intra-abdominal bacterial counts of 6.9 × 103 CFU/mL. When administered immediately after surgery, produced significant reductions in plasma endotoxin and TNF-α levels compared to control and β-lactam-treated groups. When administered 360 minutes after surgery, resulted in 40.0% lethality, 6/15 positive blood cultures, and intra-abdominal bacterial counts of 6.0 × 104 CFU/mL. When administered 360 minutes after surgery, produced significant reductions in plasma endotoxin and TNF-α levels compared to control and β-lactam-treated groups. |
| Animal Model | Wistar rats (adult male, 200-300 g)[4] |
|---|---|
| Dosage | 1 mg/kg |
| Administration | i.p.; single dose |
| Result | Showed no drug-related adverse effects. Caused no changes in measured physiological parameters including leukocyte count, serum creatinine, rectal temperature, pulse, blood pressure, breathing rate, and oxygenation. |
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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