Pyroglutamic acid

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Reference= ["Merck Index", 11th Edition, 8012.]
ImageFile=Pyroglutamic_acid.svg
ImageSize=180px
IUPACName=5-oxopyrrolidine-2-carboxylic acid
OtherNames=Pyrrolidonecarboxylic Acid, Pidolic acid, Pyroglutamate, 5-oxoproline
Section1= Chembox Identifiers
CASNo=98-79-3
PubChem=499
SMILES=C1CC(=O)NC1C(=O)O
Section2= Chembox Properties
Formula=C₅H₇NO₃
MolarMass=129.114
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Pyroglutamic acid, or pidolic acid, is an uncommon amino acid derivative in which the free amino group of glutamic acid cyclizes to form a lactam. It is found in many proteins including bacteriorhodopsin. N-terminal glutamine residues can spontaneously cyclize to become pyroglutamate. This is one of several forms of blocked N-terminals which present a problem for N-terminal sequencing using Edman chemistry, which requires a free primary amino group not present in pyroglutamic acid. The enzyme pyroglutamate aminopeptidase can restore a free N-terminus by cleaving off the pyroglutamate residue. [cite journal |author=Podell DN, Abraham GN |title=A technique for the removal of pyroglutamic acid from the amino terminus of proteins using calf liver pyroglutamate amino peptidase |journal=Biochem. Biophys. Res. Commun. |volume=81 |issue=1 |pages=176–85 |date=March 15, 1978 |pmid=26343 |doi=10.1016/0006-291X(78)91646-7]

Uses

It is sold, over the counter, as a "smart drug" for improving blood circulation in the brain.

Neutralizing pyroglutamic acid with sodium bicarbonate in water results in NaPCA, the compound human skin uses to retain moisture.Fact|date=September 2008

References