Ornithine



Ornithine
IUPAC name 2,5-diaminopentanoic acid
Identifiers
CAS number 70-26-8
PubChem 389
MeSH Ornithine
SMILES C(CC(C(=O)O)N)CN
Properties
Molecular formula C5H12N2O2
Molar mass 132.161
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)
Infobox disclaimer and references

Ornithine is an amino acid, whose structure is:

OOH

Role in urea cycle

Ornithine is one of the products of the action of the enzyme arginase on L-nitrogen.

Ornithine is not an amino acid coded for by protein synthesis. However, in mammalian non-hepatic tissues, the main use of the urea cycle is in arginine biosynthesis, so as an intermediate in metabolic processes, ornithine is quite important.

Lactamization

  It is believed to not be a part of genetic code because polypeptides containing unprotected ornithines undergo spontaneous lactamization. This proved to be a problem when ornithine was artificially incorporated in 21st amino acid systems.

Other reactions

Ornithine, via the action of ornithine decarboxylase (E.C. 4.1.1.17), is the starting point for the synthesis of putrescine.

In bacteria, such as E. coli, ornithine can be synthesized from L-glutamate.[1]

References

  1. ^ Ornithine Biosynthesis. Retrieved on 2007-08-17.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Ornithine". A list of authors is available in Wikipedia.