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Peptide Synthesis Case Studies

 Peptide Promotion
GenScript's long history of top-quality peptide synthesis has given us an opportunity to develop methods for synthesizing both common and rare peptide sequences. Below, you will find peptide synthesis case studies that exemplify our competency in synthesis and innovation in synthesis strategy development, which we have implemented through our FlexPeptide™ peptide synthesis platform. The case studies are representative of our ability to synthesize multi-cysteine peptides, multi-phosphorylated peptides, and extremely long peptides.


  • Multiple Disulfide Bonds
  • Multi-phosphorylated Peptides
  • Extremely Long Peptides

1. Multiple disulfide bonds

The synthesis of peptides containing multiple disulfide bonds can be challenging. This is due to the fact that multiple disulfide bonds can form randomly within any peptides that contain multiple cysteines. Few companies around the world offer multi- disulfide bond peptide synthesis, and none of them can synthesize peptides with more. GenScript, however, has developed two methods to synthesize peptides containing multiple disulfide bonds.

The first of these is a stepwise oxidation method utilizing different protecting groups to protect each cysteine pair during the Fmoc SPPS synthesis process. Different deprotecting conditions are used to deprotect each protecting group. These are carefully selected based on the specific needs of the client's project. With subsequent stepwise oxidizations of the disulfide bonds during the liquid phase, we can accurately synthesize peptides with more than two disulfide bonds with great accuracy.

The second method requires single-step oxidation of all of the cysteines of the peptide in liquid phase, to form a peptide containing native multiple disulfide bonds. Zymohydrolysis is subsequently employed to orient the position of disulfide bonds.

Case study: Peptide A
Sequence: H - Cys - Asn - Cys - ... ... ... - Cys - ... ... ... - Cys - ... ... ... - NH2
Disulfide bridge: 1 - 11, 3 - 15
HPLC results:


MS results:

2. Multi-phosphorylated peptides

There are two kinds of phosphopeptides: mono-phosphorylated and multi-phosphorylated. Multi-phosphorylated peptides can be very difficult to synthesize due to their high acidity and ability to reduce the rate of activation during Fmoc SPPS. GenScript has developed two strategies for reliable phosphopeptide synthesis.

The first is direct step-wise solid phase synthesis of phosphopeptides using mono-benzylated phosphoamino acids and Fmoc chemistry. This strategy involves two problems: the coupling of bzl-pAA and the coupling of the next AA. To solve them, GenScript applies microwave technology to couple bzl-pAA. This strategy makes phosphopeptide synthesis as simple as general peptide synthesis.

The second is the global phosphorylation method, which involves the postsynthetic phosphorylation of unprotected hydroxyl groups on a solid support. After synthesis, all of the phosphorylated positions in any such peptide can be phosphorylated in liquid phase in one step. This method has the advantage of avoiding the difficulties of synthesizing bzl-pAA directly.

Case study: Peptide B
Sequence: Thr- ... ... ... -pTyr- ... ... ... -pTyr-pTyr- ... ... ... -Lys
HPLC results:


MS results:

3. Extremely long peptides

The FlexPeptide™ system employs GenScript's proprietary ligation method to achieve high yields even for very long peptides. This is accomplished by first synthesizing several shorter sequences and then ligating them together via high-efficiency reactions.

Case study: Peptide C
Sequence: Ala-Glu...-Lys-....-Lys-Lys-....-Glu-Ala-...-Ala-Ala
Length: 149 AA; M.W.: 15971.51
HPLC results:


MS results: