Abstract

Glucosamine-6-phosphate (GlcN-6-P) synthase known also as L-Glutamine: D-fructose-6-phosphate aminotransferase (EC 2.6.1.16), catalyzes the first committed step in the amino sugar biosynthetic pathway in prokaryotic and eukaryotic organisms. The final product of this pathway is an activated precursor of numerous macromolecules containing amino sugars, including chitin and mannproteins in fungi, peptydoglican and lipopolysaccharides in bacteria, and glycoproteins in mammals. The important differences between prokaryotic and eukaryotic forms of the enzyme including a substantially larger size of the latter and sensitivity of the latter but not the former to the feedback inhibition by uridine 5'-diphospho-N-acetyl-D-glucosamine (UDP-GlcNAc). Finally, this enzyme has been proposed as a promising target in antifungal chemotherapy as well as for the treatment of noninsulin-dependet diabetes mellitus and gastric disorders. The condition a good drug are a very particular knowledge an enzyme structure and to influence between GlcN-6-P synthase with inhibitors. The modern crystallography is the best way whereby we can know and show structure based drug design. GlcN-6-P synthase is well known for its relative instability and difficulties in purification but it's nessesary in order to obtain a crystal of protein. One of the possible approaches to facilitate enzyme purification is a construction of its hexaHistag-containing version that can be easily isolated from complex mixtures by the one-step metal affinity chromatography. We were using the modern protein engineering technology, we have constructed C. albicans GlcN-6-P synthase containing a hexahistidyl insertion inside the ISOM domain of the enzyme, replacing the 655-660 residues of the wild-type protein. In the present work we describe construction, overexpression in E. coli, purification and characterization GlcN-6-P synthase from C. albicans with an internal hexahistydyl fragmant.

Authors (4)