Nitrogen transfer in E. coli glucosamine-6P synthase. Investigations using substrate and bisubstrate analogs

Inhibition of Escherichia coliGlucosamine-6-phosphate Synthase by Reactive Intermediate Analogues

“…(12). This value is similar to the value of the inhibitor dissociation constant (K i ϭ 25 M) determined independently by Badet-Denisot et al (11).…”

“…In accord with this mechanism, both the deaminase (40) and the synthase (5) have exchange (to solvent) to intramolecular hydrogen transfer ratios greater than 1, similar to the phosphosugar isomerases discussed above. In addition, GlcNol-6-P, an analogue of the cis-enolamine intermediate, is a potent inhibitor of both enzymes (11,12,40). In fact, GlcNol-6-P is the tightest binding reversible carbohydrate-based inhibitor reported for GlmS.…”

“…In accord with this mechanism, Badet and co-workers (14) have shown that GlmS, in the absence of glutamine, displays a low phosphoglucoisomerase activity. Analogues of the cis-enolamine reactive intermediate are expected to be potent inhibitors of the enzyme (15)(16)(17)(18) and indeed, 2-amino-2-deoxy-D-glucitol 6-phosphate (GlcNol-6-P) is the most potent carbohydrate-based inhibitor reported to date (11,12).…”

Genomic data for alternate production strategies. I. Identification of major contaminating species for Cobalt+2 immobilized metal affinity chromatography

“…The first motif has the structure HX 3 H, identified by Arnold and coworkers as a typical Cu +2 binding structure Arnold, 1990, 1991). Finally, glucosamine 6-phosphate synthase is involved in hexosamine biosynthesis (Badet-Denisot et al, 1995;Berry et al, 2000;Golinelli-Pimpaneau et al, 1989. This enzyme has the ability to transfer an amide nitrogen (e.g., glutamine) without the participation of a cofactor.…”

Investigation of Mechanism of Nitrogen Transfer in Glucosamine 6-Phosphate Synthase with the Use of Transition State Analogs

“…Badet-Denisot et al in a recent paper proposed three possible mechanisms of nitrogen transfer in GlcN-6-P synthase (7). The authors finally excluded a possibility of nitrogen labilization as a result of cyclization of glutamine into pyroglutamic acid, but two other possibilities can be still considered ( Fig.1):…”