Difference between revisions of "Part:BBa K200014"

Latest revision as of 15:40, 18 October 2009

Opiorphin + EK cleavage site + His Tag

This part codes for the pentapeptide opiorphin. An enterokinase cleavage site and HIS tag have been included for purification purposes.

Usage and Biology

Background

Opiorphin is a pentapeptide (five amino acids long) that was isolated from human saliva in 1996. Opiorphin acts as a pain killing agent. The amino acid sequence for opiorphin is Glutamine-Arginine-Phenylalanine-Serine-Arginine.

A combination of opiorphin's potency and natural presence in saliva have sparked a great deal of interest from a number of philosophical movements most notably from [http://en.wikipedia.org/wiki/David_Pearce_(philosopher) David Pearce] who belongs to the [http://en.wikipedia.org/wiki/Utilitarianism#Negative negative utilitarian] school of ethics.

Mechanism of Action

Preliminary rat studies indicate that opiorphin has a pain killing effect six times stronger than that of morphine. Enkephalins which are natural pain-killing opioids, opiorphin inhibits two enkephalin-catabolizing ectoenzymes, human neutral ecto-endopeptidase, hNEP ([http://www.ebi.ac.uk/thornton-srv/databases/cgi-bin/enzymes/GetPage.pl?ec_number=3.4.24.11 EC 3.4.24.11]), and human ecto-aminopeptidase, hAP-N ([http://www.ebi.ac.uk/thornton-srv/databases/cgi-bin/enzymes/GetPage.pl?ec_number=3.4.11.2 EC 3.4.11.2]). This results in accumulated levels of enkephalins which results in a drop in pain perception ³.

EK Cleavage

See Design Notes for our rationale behind incorporating an EK cleavage sequence and HIS tag onto the N terminus of the opiorphin pentapeptide.

Other Side Effects

Priapism:

A recent study involved genetically engineering retired breeder rats to constitutively express opiorphin. Interestingly, this resulted in the development of a priapic-like condition. It is thought that this condition resulted from the upregulation of the ornithine decarboxylase gene (ODC) by opiorphin ¹.

Antidiarrheal:

In an in-vitro bioassay it was shown that opiorphin (in concentarions 10⁻⁶ to 10⁻⁴ M) caused colonic contraction in a concentration-dependent manner ². Based on this evidence, opiorphin could have potential as an antidiarrheal agent.

Sequence and Features

Assembly Compatibility:

10
COMPATIBLE WITH RFC[10]
12
COMPATIBLE WITH RFC[12]
21
COMPATIBLE WITH RFC[21]
23
COMPATIBLE WITH RFC[23]
25
COMPATIBLE WITH RFC[25]
1000
COMPATIBLE WITH RFC[1000]

References

1 pmid=19657052

2 pmid=19442408

3 pmid=17101991

</biblio>

@@ Line 20: / Line 20: @@
 ==EK Cleavage==
-See [https://parts.igem.org/Part:BBa_K200013:Design Design Notes] for our rationale behind incorporating an EK cleavage sequence and HIS tag onto the N terminus of the opiorphin pentapeptide.
+See [https://parts.igem.org/Part:BBa_K200014:Design Design Notes] for our rationale behind incorporating an EK cleavage sequence and HIS tag onto the N terminus of the opiorphin pentapeptide.
 ==Other Side Effects==