Magainin 1 TFA (Magainin I TFA) is an antimicrobial and amphipathic peptide isolated from the skin of Xenopus laevis. Magainin 1 TFA exhibits antibiotic activity against numerous Gram-negative and Gram-positive bacteria[1][2][3].
体外研究 (In Vitro)
Magainin 1 interacts with acidic lipids through electrostatic interactions followed by hydrophobic interactions to form an amphiphilic helix, inducing the leakage. Magainin 1 induces the leakage of calcein specifically out of negatively-charged vesicles. The peptide binds to bovine brain phosphatidylserine sonicated vesicles according to the Langmuir isotherm with a binding constant of 3.8×105 M-1 and a binding-site number of 0.10 per lipid molecule[2].
MCE has not independently confirmed the accuracy of these methods. They are for reference only.
Room temperature in continental US; may vary elsewhere.
储存方式
Please store the product under the recommended conditions in the Certificate of Analysis.
参考文献
[1]. Duclohier H, et al. Antimicrobial peptide magainin I from Xenopus skin forms anion-permeable channels in planar lipid bilayers. Biophys J. 1989 Nov;56(5):1017-21.
[2]. Matsuzaki K, et al. Magainin 1-induced leakage of entrapped calcein out of negatively-charged lipid vesicles. Biochim Biophys Acta. 1989 May 19;981(1):130-4.
[3]. Zasloff M, et al. Magainins, a class of antimicrobial peptides from Xenopus skin: isolation, characterization of two active forms, and partial cDNA sequence of a precursor. Proc Natl Acad Sci U S A. 1987 Aug;84(15):5449-53.
Magainin 2 (Magainin II) is an antimicrobial peptide (AMP) isolated from the skin of the African clawed frog Xenopus laevis. Magainin 2 displays antibiotic activity against numerous gram-negative and gram-positive bacteria. Magainin 2 also is active against protozoa[1]. Magainin 2 exerts its cytotoxicity effects by preferential interactions with anionic phospholipids abundant in bacterial membranes[2].
体外研究 (In Vitro)
Magainin 2 exhibits bactericidal effects and induces morphological changes in Escherichia coli regarding early apoptosis. Magainin 2 induces the expression of a bacterial protein with affinity for the caspase substrate and effects the expression of RecA as a caspase-like protein[1]. Magainin 2 kill bacteria by permeabilizing the cell membranes without exhibiting significant toxicity against mammalian cells. The main target of the peptide is considered to be the lipid matrix of the membranes. Application of 10 μg /mL magainin 2 to Paramecium caudatum, a protozoan, in pond water caused an osmotic swelling of the cell and a subsequent cell burst, suggesting that the peptide could perturb membrane functions responsible for osmotic balance[2]. Magainin 2 permeabilizes bacterial and mammalian membranes in significantly different ways. The peptide forms pores with a diameter of about 2.8 nm (less than 6.6 nm) in B. megaterium, and translocates into the cytosol. In contrast, the peptide significantly perturbes the membrane of CHO-K1 cells, permitting the entry of a large molecule (larger than 23 nm) into the cytosol, accompanied by membrane budding and lipid flip-flop, mainly accumulating in mitochondria and nuclei[3].
MCE has not independently confirmed the accuracy of these methods. They are for reference only.
[1]. M Zasloff, et al. Magainins, a class of antimicrobial peptides from Xenopus skin: isolation, characterization of two active forms, and partial cDNA sequence of a precursor. Proc Natl Acad Sci U S A. 1987 Aug;84(15):5449-53.
[2]. K Matsuzaki, et al. Magainins as paradigm for the mode of action of pore forming polypeptides. Biochim Biophys Acta. 1998 Nov 10;1376(3):391-400.
Cell Assay [1]
Escherichia coli cells are incubated with magainin 2 (50 μg /mL). The cultures are acquired after incubation for 0, 2, 4, 6, and 8 h, respectively, and spread onto LB agar plates, and then the colony-forming units are counted after incubation for 24 h at 37°C. The percentage survival is determined relative to the control treatment[1].
MCE has not independently confirmed the accuracy of these methods. They are for reference only.
参考文献
[1]. M Zasloff, et al. Magainins, a class of antimicrobial peptides from Xenopus skin: isolation, characterization of two active forms, and partial cDNA sequence of a precursor. Proc Natl Acad Sci U S A. 1987 Aug;84(15):5449-53.
[2]. K Matsuzaki, et al. Magainins as paradigm for the mode of action of pore forming polypeptides. Biochim Biophys Acta. 1998 Nov 10;1376(3):391-400.
