Peptide structure


Opioid peptides

All peptides are chains of amino acids linked together. A few of these have the ability to affect opioid receptors in the brain and are at the same time difficult to break down. A combination of these two properties leads to protein intolerance in some individuals.

The peptides included in Neurozym's analysis are marked with an asterrisk (*).


Casein peptides

The casomorphines are formed by digestion of the casein protein. The most striking feature in these peptides is the abundance of proline. Casomorphines are known to cause addiction in severe cases of protein intolerance. The length of casomorphins are quite variable.

â-Casomorphin 1-3*
Structure: H-Tyr-Pro-Phe-OH (YPF)
Chemical formula: C23H27N3O5
Molecular weight: 425.48 g/mol

â-Casomorphin 1-4
Structure: H-Tyr-Pro-Phe-Pro-OH (YPFP)
Chemical formula: C28H34N4O6
Molecular weight: 522.60 g/mol

â-Casomorphin 1-4, amid*
Structure: H-Tyr-Pro-Phe-Pro-NH2
Chemical formula: C28H39N5O7
Molecular weight: 557.64 g/mol

â-Casomorphin 5*
Structure: H-Tyr-Pro-Phe-Pro-Gly-OH (YPFPG)
Chemical formula: C30H37N5O7
Molecular weight: 594.66 g/mol

â-Casomorphin 7*
Structure: H-Tyr-Pro-Phe-Pro-Gly-Pro-Ile-OH (YPFPGPI)
Chemical formula: C41H55N7O9
Molecular weight: 789.9 g/mol

â-Casomorphin 8*
Structure: H-Tyr-Pro-Phe-Pro-Gly-Pro-Ile-Pro-OH (YPFPGPIP)
Chemical formula: C46H62N8O10
Molecular weight: 887.00 g/mol

Gluten peptides

Gluten exorphins are formed in the enzymatic digestion of the gluten protein. Gliadorphin is similarly formed from the gliadin component of gluten.

Gluten exorphin A4
Structure: H-Gly-Tyr-Tyr-Pro-OH (GYYP)
Chemical formula: C25H30N4O7
Molecular weight: 498.54 g/mol

Gluten exorphin A5*
Structure: H-Gly-Tyr-Tyr-Pro-Thr-OH (GYYPT)
Chemical formula: C29H37N5O9
Molecular weight: 599.64 g/mol

Gluten exorphin B4
Structure: H-Tyr-Gly-Gly-Trp-OH (YGGW)
Chemical formula: C24H27N5O6
Molecular weight: 481.51 g/mol

Gluten exorphin B5*
Structure: H-Tyr-Gly-Gly-Trp-Leu-OH (YGGWL)
Chemical formula: C30H38N6O7
Molecular weight: 594.66 g/mol

Gluten exorphin C*
Structure: H-Tyr-Pro-Ile-Ser-Leu-OH (YPISL)
Chemical formula: C29H45N5O8
Molecular weight: 591.70 g/mol

Structure: H-Tyr-Pro-Gln-Pro-Gln-Pro-Phe-OH (YPQPQPF)
Chemical formula: C43H57N9O11
Molecular weight: 875.98 g/mol

Spinach peptides

Rubiscolins are a newly discovered group of opioid peptides. They are formed during digestion of the ribulose bisphosphate carboxylase/oxygenase (Rubisco) protein from spinach leaves. The effects of these peptides on mental health remains unknown.

Structure: H-Tyr-Pro-Leu-Asp-Leu-OH (YPLDL)
Chemical formula: C30H45N5O9
Molecular weight: 619.72 g/mol

Structure: H-Tyr-Pro-Leu-Asp-Leu-Phe-OH (YPLDLF)
Chemical formula: C39H54N6O10
Molecular weight: 766.89 g/mol

Other opioid peptides

Opioid peptides may come from other sources than casein, gluten and spinach. Recent research has reveiled opioid peptides also in eggs, oats and rice. We don't have structures for these peptides yet.

In addition, there is a peptide which is called dermorphin. Dermorphin is from a microbial source, but the organism(s) responsible remains elusive. It has a D-Alanin residue, which is not known in higher organisms. The guess is that dermorphin is produced by bacteria or molds. Deltorphin I and II are quite similar in structure and are from fungal sources.

Structure: H-Tyr-DAla-Phe-Gly-Tyr-Pro-Ser-NH2
Chemical formula: C40H50N8O10
Molecular weight: 802.9 g/mol

Deltorphin I
Structure: H-Tyr-DAla-Phe-Asp-Val-Val-Gly-NH2
Chemical formula: C37H52N8O10
Molecular weight: 768.9 g/mol

Deltorphin II
Structure: H-Tyr-DAla-Phe-Glu-Val-Val-Gly-NH2
Chemical formula: C38H54N8O10
Molecular weight: 782.9 g/mol

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