Cecropin P1 (porcine) targets bacterial cell membranes and lipopolysaccharide (LPS) [3].
It also inhibits porcine reproductive and respiratory syndrome virus (PRRSV) by blocking viral attachment to host cells, though specific receptor binding has not been defined [2].

In Marc-145 cells, cecropin P1, porcine (0-480 μg/mL, 36-96 hours), strongly suppresses CH-1a infection and reproduction [2]. In addition to its extracellular virucidal action against PRRSV (Porcine Reproductive and Respiratory Syndrome viral), cecropin P1, pig (0-480 μg/mL, 36 hours), has effective inhibitory activity when administered prior to, concurrently with, or following the viral Effect vaccination[2]. In the latter phases of infection, cecropin P1, pig (480 μg/mL, 0-72 hours), prevents CH-1a-induced apoptosis [2]. Porcupine cecropin P1, 0–480 μg/mL, 0–4 hours, suppresses the release of viral particles [2].

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Cecropin P1 (porcine) demonstrated antibacterial activity against Escherichia coli ATCC 25922 with a minimum inhibitory concentration (MIC) of 0.25 mg/L [3].
It showed potent inhibitory activity against PRRSV strain CH-1a in Marc-145 cells with an EC50 of 112 μg/mL; the peptide exerted extracellular virucidal activity, blocked viral attachment (but not entry), and inhibited viral particle release [2].
In porcine alveolar macrophages (PAMs), Cecropin P1 (porcine) inhibited PRRSV CH-1a replication with an EC50 of 65 μg/mL [2].
Cecropin P1 (porcine) inhibited CH-1a-induced apoptosis during late phase infection in Marc-145 cells, as shown by reduced annexin V-FITC/PI staining and decreased caspase-3 transcript levels [2].
Recombinant Cecropin P1 (porcine) expressed in Saccharomyces cerevisiae showed antibacterial activity against various Gram-negative bacteria: MIC values (μg/mL) against Salmonella (swine) = 2, Salmonella (cow) = 4, Salmonella (Moschus berezovskii) = 4, E. coli (swine) = 2, E. coli (avium) = 4, E. coli (cow) = 4, Pasteurella (rabbit) = 8, Pasteurella (cow) = 4, Shigella (swine) = 4, and Shigella (swine) = 2 [4].
Recombinant Cecropin P1 (porcine) (0.244–15.6 μg/mL) showed no significant cytotoxicity in Marc-145 cells, with cell survival rates ranging from 89.93% to 95.02% [4].
Pretreatment of Marc-145 cells with recombinant Cecropin P1 (porcine) (15.6, 3.9, 0.977, 0.244 μg/mL) for 2 h followed by PRRSV NADC30-Like infection resulted in cell survival rates of 92.26%, 88.68%, 83.71%, and 68.84% at 72 h, respectively, indicating dose-dependent antiviral activity [4].

In rats suffering from septic shock, cecropin P1 (1 mg/kg, intraperitoneally, once) inhibits the growth of bacteria, endotoxemia, and mortality [3].

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In a rat model of septic shock, intraperitoneal administration of Cecropin P1 (porcine) at 1 mg/kg immediately after intraperitoneal challenge with 2×10^10 CFU of Escherichia coli ATCC 25922 resulted in 93.3% survival (14/15) at 48 h, compared to 13.3% survival in untreated controls. Cecropin P1 (porcine) significantly reduced bacterial counts in peritoneal fluid (3.1×10^3 ± 0.9×10^3 CFU/mL vs. 4.5×10^6±1.1×10^6 CFU/mL in controls) and lowered plasma endotoxin levels to ≤0.015 EU/mL and TNF-α levels to ≤4 pg/mL at 240 min post-infection [3].

The MIC of Cecropin P1 (porcine) against E. coli ATCC 25922 was determined using the broth microdilution method according to National Committee for Clinical Laboratory Standards (NCCLS) guidelines, with modifications for cationic peptides: polypropylene 96-well plates were used instead of polystyrene, and serial dilutions were prepared in 0.01% acetic acid containing 0.2% bovine serum albumin. Plates were incubated for 18 h at 37°C in air. The MIC was taken as the lowest concentration at which observable growth was inhibited. Experiments were performed in triplicate [3].
For susceptibility testing of recombinant Cecropin P1 (porcine) against various bacteria, the microdilution test according to Clinical and Laboratory Standards Institute (CLSI) guidelines was used. Minimum inhibitory concentrations were determined by serial two-fold dilutions of the peptide in appropriate media, and bacterial growth was assessed after incubation [4].

Cell viability assay[2]
Cell Types: Marc-145 Cell
Tested Concentrations: 160, 320 and 480 μg/mL
Incubation Duration: 36, 48, 72, 96 hrs (hours)
Experimental Results: 36 hrs (hours) Dramatically inhibited viral infection in a dose-dependent manner Post-infection . Inhibits CH-1a infection in Marc-145 cells with a 50% effective concentration (EC50) of 112 μg/mL. The 50% cytotoxic concentration (CC50) of cecropin P1 on Marc-145 cells was estimated to be 719 μg/mL.

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Western Blot Analysis[2]
Cell Types: Marc-145 Cell
Tested Concentrations: 160, 320 and 480 μg/mL
Incubation Duration: 36 hrs (hours)
Experimental Results: Significant inhibition of viral infection in a dose-dependent manner at 36 hrs (hours) post-infection. The expression of viral N protein was Dramatically diminished when pre-treatment, during-treatment or post-treatment methods were used.

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Cecropin P1 (porcine) was evaluated for antiviral activity in Marc-145 cells and porcine alveolar macrophages (PAMs). For cytotoxicity assay, cells at 60-70% confluence were treated with serial concentrations of Cecropin P1 (porcine) (up to 480 μg/mL for Marc-145 or 280 μg/mL for PAMs) for 48 h, then 10 μL of alamarBlue was added and incubated for 3 h; fluorescence was measured at 570/590 nm. The CC50 was calculated using GraphPad Prism [2].
For antiviral assays, three treatment regimens were used: (I) Pretreatment: cells treated with Cecropin P1 (porcine) for 2 h then infected with PRRSV CH-1a (MOI=0.01) for 36 h; (II) Cotreatment: cells inoculated simultaneously with virus and peptide for 36 h; (III) Posttreatment: cells infected for 8 h then treated with peptide for 36 h. Viral yields were determined by TCID50, viral RNA by qRT-PCR (ORF7), and viral N protein by immunoblotting with anti-PRRSV N protein mAb (SDOW17) [2].
Apoptosis assay: Marc-145 cells infected with CH-1a (MOI=0.01) in presence of Cecropin P1 (porcine) (480 μg/mL) for 24, 48, or 72 h, then stained with annexin V-FITC and PI for 15 min in dark, observed under fluorescence microscopy [2].
Viral attachment/entry assays: For attachment, cells cooled at 4°C for 30 min, challenged with CH-1a (MOI=0.01) plus peptide at 4°C for 3 h, then shifted to 37°C for 24 h. For entry, cells challenged at 4°C for 3 h, then incubated at 37°C with peptide added at 0, 2, or 4 h after temperature shift. Viral RNA and protein were analyzed [2].
MTT cytotoxicity assay for recombinant Cecropin P1 (porcine) in Marc-145 cells: cells at 80-90% confluence treated with peptide concentrations (15.6, 3.9, 0.977, 0.244 μg/mL) for 2 h, then fresh medium added. When positive control showed 80% CPE, 15 μL of 50 μM MTT added per well, incubated 3-4 h at 37°C, then DMSO added and OD490 measured. Cell survival rate = (OD490 of peptide group / OD490 of cell control) ×100% [4].
Antiviral pretreatment assay: Marc-145 cells treated with Cecropin P1 (porcine) (C1-C4 concentrations) for 2 h, then infected with PRRSV NADC30-Like at TCID50 concentration. Cytopathic effect was recorded every 12 h, and cell survival rate calculated by MTT assay at 72 h [4].

Rat septic shock model: Adult male Wistar rats (250-300 g) were anesthetized with ketamine (30 mg/kg IM). The abdomen was shaved and prepared with iodine. Rats received an intraperitoneal inoculum of 1 mL saline containing 2×10^10 CFU of E. coli ATCC 25922. Immediately after bacterial challenge, animals were randomized to receive intraperitoneally: isotonic sodium chloride (untreated control), or 1 mg/kg Cecropin P1 (porcine) dissolved in physiologic saline. Each group contained 15 animals. Animals were monitored for 48 h post-infection. Blood samples were collected from the jugular vein at 0, 60, 120, and 240 min post-injection for endotoxin and TNF-α measurement. Surviving animals were killed with chloroform; blood samples for culture were obtained by aseptic percutaneous transthoracic cardiac puncture; 10 mL sterile saline was injected intraperitoneally for peritoneal lavage, and lavage fluid was serially diluted and plated on blood agar for bacterial enumeration [3].
For PRRSV studies: No in vivo animal experiments were performed; all assays were in vitro using Marc-145 cells and porcine alveolar macrophages isolated from 3-8 week-old PRRSV-negative piglets by lung lavage [2].

[1]. Andersson M, et al. Ascaris nematodes from pig and human make three antibacterial peptides: isolation of cecropin P1 and two ASABF peptides. Cell Mol Life Sci. 2003 Mar;60(3):599-606.
[2]. Guo C, et al. Cecropin P1 inhibits porcine reproductive and respiratory syndrome virus by blocking attachment. BMC Microbiol. 2014 Nov 18;14:273.
[3]. Giacometti A, et al. Effect of mono-dose intraperitoneal cecropins in experimental septic shock. Crit Care Med. 2001 Sep;29(9):1666-9.
[4]. Jiang R, et al. Expression of antimicrobial peptide Cecropin P1 in Saccharomyces cerevisiae and its antibacterial, antiviral activity in vitro. Electronic Journal of Biotechnology, 2020.

Cecropin P1 (porcine) was originally misidentified as a mammalian peptide from pig intestine; later work revealed it is produced by the parasitic nematodes Ascaris suum and Ascaris lumbricoides, which live in the gut of pigs and humans respectively. The peptide works in concert with cysteine-rich ASABF peptides to provide broad-spectrum antibacterial protection against Gram-negative and Gram-positive bacteria [1].
The peptide has a free C-terminal carboxyl group, unlike insect cecropins which are amidated [1].
Cecropin P1 (porcine) also displays extracellular virucidal activity against PRRSV, possibly by directly inactivating viral particles [2].
In septic shock model, Cecropin P1 (porcine) reduced plasma endotoxin and TNF-α levels, indicating anti-endotoxin activity in addition to antibacterial effects [3].
Recombinant expression in Saccharomyces cerevisiae using galactose induction is a safe, non-toxic method to produce active Cecropin P1 (porcine) with both antibacterial and antiviral properties [4].

C147H253N45O43

3338.8575

3336.9

125667-96-1

Cecropin P1, porcine acetate

16130477

Typically exists as solid at room temperature

3.073

52

51

120

235

7600

33

O=C([C@]1([H])C([H])([H])C([H])([H])C([H])([H])N1C(C([H])([H])N([H])C(C([H])([H])N([H])C([C@]([H])(C([H])([H])C([H])([H])C(N([H])[H])=O)N([H])C([C@]([H])([C@@]([H])(C([H])([H])[H])C([H])([H])C([H])([H])[H])N([H])C([C@]([H])(C([H])([H])[H])N([H])C([C@]([H])([C@@]([H])(C([H])([H])[H])C([H])([H])C([H])([H])[H])N([H])C([C@]([H])(C([H])([H])[H])N([H])C([C@]([H])([C@@]([H])(C([H])([H])[H])C([H])([H])C([H])([H])[H])N([H])C(C([H])([H])N([H])C([C@]([H])(C([H])([H])C([H])([H])C(=O)O[H])N([H])C([C@]([H])(C([H])([H])O[H])N([H])C([C@]([H])([C@@]([H])(C([H])([H])[H])C([H])([H])C([H])([H])[H])N([H])C([C@]([H])(C([H])([H])C([H])([H])C([H])([H])N([H])/C(=N/[H])/N([H])[H])N([H])C([C@]([H])(C([H])([H])C([H])([H])C([H])([H])C([H])([H])N([H])[H])N([H])C([C@]([H])(C([H])([H])C([H])([H])C([H])([H])C([H])([H])N([H])[H])N([H])C([C@]([H])(C([H])([H])[H])N([H])C([C@]([H])(C([H])([H])O[H])N([H])C([C@]([H])(C([H])([H])C(N([H])[H])=O)N([H])C([C@]([H])(C([H])([H])C([H])([H])C(=O)O[H])N([H])C([C@]([H])(C([H])([H])C([H])(C([H])([H])[H])C([H])([H])[H])N([H])C([C@]([H])(C([H])([H])C([H])([H])C([H])([H])C([H])([H])N([H])[H])N([H])C([C@]([H])(C([H])([H])C([H])([H])C([H])([H])C([H])([H])N([H])[H])N([H])C([C@]([H])(C([H])([H])[H])N([H])C([C@]([H])([C@@]([H])(C([H])([H])[H])O[H])N([H])C([C@]([H])(C([H])([H])C([H])([H])C([H])([H])C([H])([H])N([H])[H])N([H])C([C@]([H])(C([H])([H])O[H])N([H])C([C@]([H])(C([H])([H])C([H])(C([H])([H])[H])C([H])([H])[H])N([H])C([C@]([H])(C([H])([H])C1=C([H])N([H])C2=C([H])C([H])=C([H])C([H])=C12)N([H])C([C@]([H])(C([H])([H])O[H])N([H])[H])=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)=O)N([H])[C@]([H])(C(=O)O[H])C([H])([H])C([H])([H])C([H])([H])N([H])/C(=N/[H])/N([H])[H]

PRIVBYDFWSFUFP-RJLJEYQFSA-N

InChI=1S/C147H253N45O43/c1-18-75(9)113(140(229)167-81(15)120(209)188-114(76(10)19-2)141(230)168-82(16)121(210)189-115(77(11)20-3)142(231)178-94(47-50-106(154)198)123(212)164-66-108(200)163-68-110(202)192-60-36-46-105(192)139(228)179-97(145(234)235)45-35-59-161-147(158)159)187-109(201)67-165-124(213)95(48-51-111(203)204)176-138(227)104(72-196)186-143(232)116(78(12)21-4)190-130(219)93(44-34-58-160-146(156)157)174-127(216)90(41-26-31-55-150)172-125(214)88(39-24-29-53-148)170-118(207)79(13)166-136(225)102(70-194)184-135(224)101(64-107(155)199)183-129(218)96(49-52-112(205)206)177-132(221)98(61-73(5)6)181-128(217)91(42-27-32-56-151)173-126(215)89(40-25-30-54-149)171-119(208)80(14)169-144(233)117(83(17)197)191-131(220)92(43-28-33-57-152)175-137(226)103(71-195)185-133(222)99(62-74(7)8)182-134(223)100(180-122(211)86(153)69-193)63-84-65-162-87-38-23-22-37-85(84)87/h22-23,37-38,65,73-83,86,88-105,113-117,162,193-197H,18-21,24-36,39-64,66-72,148-153H2,1-17H3,(H2,154,198)(H2,155,199)(H,163,200)(H,164,212)(H,165,213)(H,166,225)(H,167,229)(H,168,230)(H,169,233)(H,170,207)(H,171,208)(H,172,214)(H,173,215)(H,174,216)(H,175,226)(H,176,227)(H,177,221)(H,178,231)(H,179,228)(H,180,211)(H,181,217)(H,182,223)(H,183,218)(H,184,224)(H,185,222)(H,186,232)(H,187,201)(H,188,209)(H,189,210)(H,190,219)(H,191,220)(H,203,204)(H,205,206)(H,234,235)(H4,156,157,160)(H4,158,159,161)/t75-,76-,77-,78-,79-,80-,81-,82-,83+,86-,88-,89-,90-,91-,92-,93-,94-,95-,96-,97-,98-,99-,100-,101-,102-,103-,104-,105-,113-,114-,115-,116-,117-/m0/s1

(4S)-5-[[(2S)-4-amino-1-[[(2S)-1-[[(2S)-1-[[(2S)-6-amino-1-[[(2S)-6-amino-1-[[(2S)-1-[[(2S,3S)-1-[[(2S)-1-[[(2S)-1-[[2-[[(2S,3S)-1-[[(2S)-1-[[(2S,3S)-1-[[(2S)-1-[[(2S,3S)-1-[[(2S)-5-amino-1-[[2-[[2-[(2S)-2-[[(1S)-4-carbamimidamido-1-carboxybutyl]carbamoyl]pyrrolidin-1-yl]-2-oxoethyl]amino]-2-oxoethyl]amino]-1,5-dioxopentan-2-yl]amino]-3-methyl-1-oxopentan-2-yl]amino]-1-oxopropan-2-yl]amino]-3-methyl-1-oxopentan-2-yl]amino]-1-oxopropan-2-yl]amino]-3-methyl-1-oxopentan-2-yl]amino]-2-oxoethyl]amino]-4-carboxy-1-oxobutan-2-yl]amino]-3-hydroxy-1-oxopropan-2-yl]amino]-3-methyl-1-oxopentan-2-yl]amino]-5-carbamimidamido-1-oxopentan-2-yl]amino]-1-oxohexan-2-yl]amino]-1-oxohexan-2-yl]amino]-1-oxopropan-2-yl]amino]-3-hydroxy-1-oxopropan-2-yl]amino]-1,4-dioxobutan-2-yl]amino]-4-[[(2S)-2-[[(2S)-6-amino-2-[[(2S)-6-amino-2-[[(2S)-2-[[(2S,3R)-2-[[(2S)-6-amino-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-amino-3-hydroxypropanoyl]amino]-3-(1H-indol-3-yl)propanoyl]amino]-4-methylpentanoyl]amino]-3-hydroxypropanoyl]amino]hexanoyl]amino]-3-hydroxybutanoyl]amino]propanoyl]amino]hexanoyl]amino]hexanoyl]amino]-4-methylpentanoyl]amino]-5-oxopentanoic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment (e.g. under nitrogen), avoid exposure to moisture and light.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

H2O : ~50 mg/mL (~14.98 mM)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

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Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

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Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

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Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

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Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

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Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

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 (Please use freshly prepared in vivo formulations for optimal results.)