Glutamine cyclotransferase

The purification of glutamine cyclotransferase from papaya latex has been carried out by Messer and Ottesen (116). A batch procedure was used for the removal of impurities by passage of a papaya latex extract through a thin layer of carboxymethyl-Sephadex the active protein was separated by selective elution. Additional purification was achieved by chromatography on a column of carboxymethyl-Sephadex and by gel filtration on Sephadex G-100. The purified enzyme was homogeneous by the criteria of paper electrophoresis, ultracentrifugation, and gel filtration on Sephadex G-100 columns and chromatography on carboxy-methyl- or DEAE-Sephadex. The electrophoretic behavior of the enzyme indicates that it is a basic protein with an isoelectric point near... 

An enzyme possessing the properties of L-glutamine cyclotransferase has not as yet been found in animal tissue. However, the conversion of glutamine to pyrrolidone caboxylic acid by a two-step enzyme-catalyzed pathway has been observed (13). Thus, glutamine may be converted to y-glutamyl glutamine by y-glutamyl transpeptidase ... 

TAGZyme kit/E. coli MK(HQ)6QJ,-Protein and various, other His tags optimized for this kit Dipeptidyl aminopeptidase 1 (DPP 1) alone or a combination of DPP 1, glutamine cyclotransferase (GCT) and pyroglutamyl aminopeptidase (PGAP) UNYZYME Laboratories, Horsholm... 

Zerhouni, S. Amrani, A. Nijs, M. Smolders, N. Azarkan, M. Vincentelli, J. Looze, Y. Purification and characterization of papaya glutamine cyclotransferase, a plant enzyme highly resistant to chemical, acid and thermal denaturation. Biochem. Biophys. Acta 1998, 1387, 275-290. 

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