Pyroglutamic acid

Jump to: navigation, search

Please Take Over This Page and Apply to be Editor-In-Chief for this topic: There can be one or more than one Editor-In-Chief. You may also apply to be an Associate Editor-In-Chief of one of the subtopics below. Please mail us [1] to indicate your interest in serving either as an Editor-In-Chief of the entire topic or as an Associate Editor-In-Chief for a subtopic. Please be sure to attach your CV and or biographical sketch.

Template:Chembox E number
Pyroglutamic acid[1]
IUPAC name 5-oxopyrrolidine-2-carboxylic acid
Other names Pyrrolidonecarboxylic Acid, Pidolic acid, Pyroglutamate, 5-oxoproline
3D model (JSmol)
ECHA InfoCard Lua error in Module:Wikidata at line 879: attempt to index field 'wikibase' (a nil value). Lua error in Module:Wikidata at line 879: attempt to index field 'wikibase' (a nil value).
Molar mass 129.114
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox disclaimer and references

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.[2]


  1. Merck Index, 11th Edition, 8012.
  2. Podell DN, Abraham GN (March 15, 1978). "A technique for the removal of pyroglutamic acid from the amino terminus of proteins using calf liver pyroglutamate amino peptidase". Biochem. Biophys. Res. Commun. 81 (1): 176–85. doi:doi:10.1016/0006-291X(78)91646-7 Check |doi= value (help). PMID 26343. Check date values in: |date= (help)