Cyclization of N-Terminal Glutamic Acid to pyro-Glutamic Acid
Pyroglutamic acid (pyroGlu) is commonly observed at the N-terminus of therapeutic monoclonal antibodies. Notably, the term "pyroGlu" refers to a single product that could originate from the cyclization of either an N-terminal glutamine or an N-terminal glutamic acid. This is …
Formation of Pyroglutamic Acid from N-Terminal Glutamic Acid …
Feb 24, 2006 · We identified the formation of pyroglutamic acid from N-terminal glutamic acid in the heavy chains and light chains of several antibodies, indicating that this nonenzymatic reaction does occur very commonly and can be detected after a few weeks of incubation at 37 and 45 °C.
Pyroglutamic acid - Wikipedia
Pyroglutamic acid (also known as PCA, 5-oxoproline, pidolic acid) is a ubiquitous but understudied natural amino acid derivative in which the free amino group of glutamic acid or glutamine cyclizes to form a lactam. [1] The names of pyroglutamic acid conjugate base, anion, salts, and esters are pyroglutamate, 5-oxoprolinate, or pidolate.
N-terminal Glutamate to Pyroglutamate Conversion
Both glutamine and glutamate at the N termini of recombinant monoclonal antibodies can cyclize spontaneously to pyroglutamate (pE) in vitro. Glutamate conversion to pyroglutamate occurs more slowly than from glutamine but has been observed under near physiological conditions.
Cyclization of N-Terminal Glutamic Acid to pyro-Glutamic Acid …
Oct 1, 2019 · Formation of a pyroglutamic acid (pyroGlu) at the mAb N-terminus creates a unique challenge in charge variant analysis. This is because there are 2 distinct pathways to cyclize the N-terminal amino acid to form a pyroGlu (Fig. 1), and they produce different charge variants between a pyroGlu and its uncyclized forms.
N-terminal glutamate to pyroglutamate conversion in vivo for ... - PubMed
Apr 1, 2011 · Both glutamine and glutamate at the N termini of recombinant monoclonal antibodies can cyclize spontaneously to pyroglutamate (pE) in vitro. Glutamate conversion to pyroglutamate occurs more slowly than from glutamine but has been observed under near physiological conditions.
Cyclization of N-Terminal Glutamic Acid to pyro-Glutamic Acid …
Pyroglutamic acid (pyroGlu) is commonly observed at the N-terminus of therapeutic monoclonal antibodies. Notably, the term "pyroGlu" refers to a single product that could originate from the cyclization of either an N-terminal glutamine or an N-terminal glutamic acid.
Occurrence, properties and biological significance of …
Sep 1, 2019 · Pyroglutamyl (pGlu) peptides are formed from intramolecular cyclization of glutamine or glutamic acid residue at the N-terminal position of peptides. This process can occur endogenously or during processing of foods containing the peptides.
Glutamic Acid as a Precursor to N-Terminal Pyroglutamic Acid in …
Cell suspensions derived from a mouse plasmacytoma (RPC-20) that secretes an immunoglobulin light chain containing N-terminal pyroglutamic acid can synthesize protein in vitro. Chromatographic examination of an enzymatic digest of protein labeled with glutamic acid shows only labeled glutamic acid and pyroglutamic acid; hydrolysis of protein ...
Briefly, in the gamma-glutamyl cycle, pyroglutamic acid is formed after the enzymatic removal (see below) of the N-terminal gamma-glutamate residue bonded to anyone of a number of amino acids by the cytoplasmic enzyme gamma-glutamyl cyclotransferase (GCT). The pyroglutamate formed is then converted to L glutamic acid by 5-oxo-L-prolinase.