Cecropin B peptide

Cecropin B peptide

• Handling and Storage of Synthetic Peptides
• Material Safety Data Sheets (MSDS)

H-KWKVFKKIEKMGRNIRNGIVKAGPAIAVLGEAKAL-COCH3

H-Lys-Trp-Lys-Val-Phe-Lys-Lys-Ile-Glu-Lys-Met-Gly-Arg-Asn-Ile-Arg-Asn-Gly-Ile-Val-Lys-Ala-Gly-Pro-Ala-Ile-Ala-Val-Leu-Gly-Glu-Ala-Lys-Ala-Leu-COCH3

35

95.88%

C₁₇₆H₃₀₁N₅₁O₄₂S

3835.64

Synthetic

Powder

Cecropins were first discovered in Cecropia moth pupae. The source of Cecropin B is the giant silk moth, Hyalophora cecropia.
Cecropin B is an antimicrobial peptide (AMP) with a molecular weight of 3.84 kDa and a net positive charge of +7 at pH 7.0. It has shown antimicrobial activity against various bacterial strains, including those resistant to conventional antibiotics. For example, Cecropin B is active against insect pathogens S. marcescens, P. aeruginosa, X. nematophilus, as well as other strains such as E. colo K12, B. megaterium (inhibition zone assays).
Cecropin B inserts into anionic model membranes using its amphipathic N-terminal segment and the hydrophobic C-terminal segment of a second peptide. The mode of action of Cecropin B is membrane-specific, involving the formation of a pore in the membrane. The hydrophobic C-terminal segment plays a crucial role in its antimicrobial activity by interacting with the membrane.
The cecropins' antibacterial proteins are an emerging non-antibiotic therapeutic strategy to overcome antibiotic resistance. The cationic nature of Cecropin B, as an AMP, is attributed to the complex interaction of different structural motifs and the potential role of electronegative side chains.

Normally, this peptide will be delivered in lyophilized form and should be stored in a freezer at or below -20 °C. For more details, please refer to the manual:Handling and Storage of Synthetic Peptides

• Steiner H, Hultmark D, Engström A, Bennich H, Boman HG. Sequence and specificity of two antibacterial proteins involved in insect immunity. Nature. 1981;292(5820):246-8.
• Gudmundsson GH, Lidholm DA, Asling B, Gan R, Boman HG. The cecropin locus. Cloning and expression of a gene cluster encoding three antibacterial peptides in Hyalophora cecropia. J Biol Chem. 1991 Jun 25;266(18):11510-7.
• Sallum UW, Chen TT. Inducible resistance of fish bacterial pathogens to the antimicrobial peptide cecropin B. Antimicrob Agents Chemother. 2008 Sep;52(9):3006-12.
• Hsiao YW, Hedström M, Losasso V, Metz S, Crain J, Winn M. Cooperative Modes of Action of Antimicrobial Peptides Characterized with Atomistic Simulations: A Study on Cecropin B. J Phys Chem B. 2018 Jun 7;122(22):5908-5921.
• Jugl A, Pekař M. Hyaluronan-cecropin B interactions studied by ultrasound velocimetry and isothermal titration calorimetry. Int J Biol Macromol. 2023 Feb 1;227:786-794.
• Okasha H, Dahroug H, Gouda AE, Shemis MA. A novel antibacterial approach of Cecropin-B peptide loaded on chitosan nanoparticles against MDR Klebsiella pneumoniae isolates. Amino Acids. 2023 Dec;55(12):1965-1980.

Trifluoroacetic acid (TFA) has a significant impact on peptides due to its role in the peptide synthesis process.

TFA is essential for the protonation of peptides that lack basic amino acids such as Arginine (Arg), Histidine (His), and Lysine (Lys), or ones that have blocked N-termini. As a result, peptides often contain TFA salts in the final product.

TFA residues, when present in custom peptides, can cause unpredictable fluctuations in experimental data. At a nanomolar (nM) level, TFA can influence cell experiments, hindering cell growth at low concentrations (as low as 10 nM) and promoting it at higher doses (0.5–7.0 mM). It can also serve as an allosteric regulator on the GlyR of glycine receptors, thereby increasing receptor activity at lower glycine concentrations.

In an in vivo setting, TFA can trifluoroacetylate amino groups in proteins and phospholipids, inducing potentially unwanted antibody responses. Moreover, TFA can impact structure studies as it affects spectrum absorption.