Misplaced Pages

Pseudin

Article snapshot taken from[REDACTED] with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.

Pseudin is a peptide derived from Pseudis paradoxa. Pseudins have some antimicrobial function.

There are several different forms:

  • pseudin-1
  • pseudin-2 -- has been proposed as a treatment for type 2 diabetes.
  • pseudin-4

Pseudin-2

Pseudin-2 is the most abundant version of the pseudins found on the skin of the paradoxical frog. The primary sequence reads as GLNALKKVFQGIHEAIKLINNHVQ. Its secondary/tertiary structure consists of one cationic amphipathic α-helix.

Antibacterial activity

Pseudin-2 was shown to have potent antibacterial activity, but a lower cytotoxicity. The cytotoxicity of a peptide can be measured by its effect on human erythrocytes. It takes a lower concentration of Pseudin-2 to kill bacteria or fungi such as E. coli, S. aureus, and C. albicans than to kill human erythrocytes. It is hypothesized that Pseudin-2 binding to the cell membrane of the bacteria results in a conformational change in which the peptide forms an α-helical shape, which allows it to perform cell lysis by inserting itself in the hydrophobic portion of the membrane. This mechanism is applicable to similar amphipathic α-helical peptides created by many frog species, although most of these peptides aren't very potent against bacteria. By increasing the cationicity and amphipathic nature of the molecule, it is possible to create analogues of Pseudin-2 that are even more selective towards bacteria. This is done by substituting leucine residues with lysine residues and glycine residues with proline residues, which results in two shorter α-helices (linked by the substituted proline) that are more attuned to penetrating bacterial cell membranes.

See also

References

  1. "InterPro: IPR013156 Pseudin antimicrobial peptide". Retrieved 2008-03-02.
  2. senior reporters; G.C. Barrett; J.S. Davies. (2004). Amino acids, peptides and proteins. Cambridge, Eng: Royal Society of Chemistry. pp. 72. ISBN 0-85404-242-3.
  3. Rinaldi AC (2002). "Antimicrobial peptides from amphibian skin: an expanding scenario". Curr Opin Chem Biol. 6 (6): 799–804. doi:10.1016/S1367-5931(02)00401-5. PMID 12470734.
  4. "Pseudin-1 - Pseudis paradoxa (Paradoxical frog)". Retrieved 2008-03-02.
  5. Abdel-Wahab YH, Power GJ, Ng MT, Flatt PR, Conlon JM (2008). "Insulin-releasing properties of the frog skin peptide pseudin-2 and its -substituted analogue". Biol. Chem. 389 (2): 143–8. doi:10.1515/BC.2008.018. PMID 18163889. S2CID 5411214.
  6. Rose, David (2008-03-03). "Jungle frog's anti-infection agent may help millions of diabetics - Times Online". The Times. London. Archived from the original on May 16, 2008. Retrieved 2008-03-02.
  7. "Pseudin-4 - Pseudis paradoxa (Paradoxical frog)". Retrieved 2008-03-02.
  8. ^ Olson, L.; Soto, A. M.; Knoop, F. C.; Conlon, J. M. (2001-11-09). "Pseudin-2: an antimicrobial peptide with low hemolytic activity from the skin of the paradoxical frog". Biochemical and Biophysical Research Communications. 288 (4): 1001–1005. doi:10.1006/bbrc.2001.5884. ISSN 0006-291X. PMID 11689009.
  9. ^ Jeon, Dasom; Jeong, Min-Cheol; Jacob, Binu; Bang, Jeong Kyu; Kim, Eun-Hee; Cheong, Chaejoon; Jung, In Duk; Park, Yoonkyung; Kim, Yangmee (2017-05-03). "Investigation of cationicity and structure of pseudin-2 analogues for enhanced bacterial selectivity and anti-inflammatory activity". Scientific Reports. 7 (1): 1455. Bibcode:2017NatSR...7.1455J. doi:10.1038/s41598-017-01474-0. ISSN 2045-2322. PMC 5431190. PMID 28469145.
  10. Conlon, J. Michael (2011-07-11). "Structural diversity and species distribution of host-defense peptides in frog skin secretions". Cellular and Molecular Life Sciences. 68 (13): 2303–2315. doi:10.1007/s00018-011-0720-8. ISSN 1420-9071. PMC 11114843. PMID 21560068. S2CID 24189013.


Stub icon

This biochemistry article is a stub. You can help Misplaced Pages by expanding it.

Categories:
Pseudin Add topic