Adipokinetic Hormone (AKH), Locusta peptide

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

Adipokinetic hormone (AKH) is an insect neuropeptide produced by the corpora cardiaca, two neurohemal organs, often fused, that are closely situated to the insect brain. They bring on the release of diglycerides and then stimulate the flight muscles to use them as an energy source. There are other types of active peptides structurally related to AKH. These peptides are eight to ten amino acid residues long.

The table below shows some AKH and AKH-like peptides.

• Li S, Hauser F, Skadborg SK, Nielsen SV, Kirketerp-Møller N, Grimmelikhuijzen CJ. Adipokinetic hormones and their G protein-coupled receptors emerged in Lophotrochozoa. Sci Rep. 2016

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.