Custom Long Peptide Synthesis

Solid phase synthesis is the most common and convenient method in protein chemical synthesis. This method is also effective for custom long peptide synthesis, but as the chain lengthens, the reaction becomes progressively more difficult (for example, greater than 150 amino acids) and some target peptides are produced that are deficient in residues. These residues are also the main impurities in the synthesis of long peptides.

In the synthesis of long peptides, the main difficulty we need to overcome is to explore better reaction conditions and methods so as to make the condensation reaction of amino acids more complete. The reaction time also needs to be shortened, because the longer the reaction time, the more uncontrollable side reactions there are and the more complex the by-products, which are also an important part of the impurities produced by the whole reaction.

Advantages of Omizzur long peptide technology

√ Using SPPS and hydrazide natural chemical strategy, Omizzur have successfully synthesized  Tetra-ubiquitin(304AA) ,Tri-ubiquitin(228AA),Ribosome protein S25(142AA),Histon H3 (135AA).

√ In custom peptide synthesis, microwave radiation is used to complete long peptide sequences with high absorption and low racemization.Microwaves can penetrate deep into the interior of substance, so it takes only one tenth to one percent of the time for regular methods to complete the entire heating process.

In view of the different problems in the synthesis of long peptides, Omizzur adopted a series of effective synthesis strategies.

1. Microwave Peptide Synthesis

Using OMIZZU^TM optimized microwave technology, peptide absorption after microwave energy will change with the changes in microwave field strength, this helps break the peptide chain polymerization ‚ make its possible for difficult peptide and long peptide synthesis, such as containing large space steric amino acid Arg ‚ hydrophobic amino acids Ala, Val, Ile, or beta folding sequence.

2. Peptide Fragment Synthesis

The traditional step-by-step extension method may can not meet the synthesis requirements when the peptide chain is long and highly demanding,The peptide chain can be divided into several peptide segments according to the sequence, and then the condensation reaction is carried out, which increases the yield of long and difficult peptide.This method can solve many synthesis problems of long peptides.

3. Hydrazide Chemical Synthesis

The synthesis of peptides by acyl hydrazine method is a method of solid phase synthesis of N-terminal Cys polypeptide and C-terminal acyl hydrazine peptide by chemical selective reaction to form amide bond. According to the position of Cys in the peptide chain, the whole peptide chain was divided into multiple sequences for synthesis, and the target peptide was finally obtained through liquid phase condensation reaction. This method not only greatly shortened the synthesis time of long peptide, but also significantly improved the purity of the final product, so it is widely applicable to the synthesis of long peptide containing Cys.

References

1. Ahreuter DH,Dordick JS,Clark DS,Solld-phase peptide Synthesis by ion-paired alpha-chymotrypsin in nonaqueous media[J]．Biotechnol Bioeng，2003，81(7)：809-817

2. Boeijen A,van Ameijde [J],Liskamp RM.Soild phase synthesis of oligourea peptidomimetics employing the Fmoc protection strategy[J].JOrg Chem,2001,66(25):8454-8462

3. De la Torre Beatriz G，Mareos Miguel A，Eritja Ramon，et al.Solid phase peptide synthesis using Na-trityl-amino acids [J].Lett Pept Sci,2001,8(6):331-338