The dipeptide pGlu-Pro-NH2

Research output: Contribution to journalArticlepeer-review


The crystal structure of the pGlu-Pro-NH2 dipeptide, cis-1-(5-oxo-L-prolyl)-L-prolinamide hydrate [cis-1-(5-oxo-L-prolyl)pyrrolidine-2-carboxamide hydrate], C10H15-N3Oa.H2O, has been determined in order to establish the conformation of the pyrrolidine ring both in natural (L) proline (Pro) and in pyroglutamic acid (pGlu), a cyclic analogue of the the natural L-glutamate amino acid. The structure was solved by direct methods and refined by least-squares calculations to a final R value of 0.026. While the pyrrolidine ring of the Pro residue adopts a twisted conformation, this ring is planar in the pGlu amino acid. The proline residue is in a cis orientation with respect to the peptide bond. Molecular cohesion is stabilized by a dense network of hydrogen bonds involving the free amine group of pGlu, the three O atoms of the carbonyl groups, the terminal carboxy-protective NH2 group and a water molecule.

Original languageEnglish
Pages (from-to)477-480
Number of pages4
JournalActa crystallographica Section C: Crystal Structure communications
Issue number4
Publication statusPublished - 15 Apr 1997


Dive into the research topics of 'The dipeptide pGlu-Pro-NH<sub>2</sub>'. Together they form a unique fingerprint.

Cite this