Studies on the substrate specificity of a GDP-mannose pyrophosphorylase from Salmonella enterica

Abstract

SummaryA series of methoxy and deoxy derivatives of mannopyranose-1-phosphate (Manp-1P) were chemically synthesized, and their ability to be converted into the corresponding guanosine diphosphate mannopyranose (GDP-Manp) analogues by a pyrophosphorylase (GDP-ManPP) from Salmonella enterica was studied. Evaluation of methoxy analogues demonstrated that GDP-ManPP is intolerant of bulky substituents at the C-2, C-3, and C-4 positions, in turn suggesting that these positions are buried inside the enzyme active site. Additionally, both the 6-methoxy and 6-deoxy Manp-1P derivatives are good or moderate substrates for GDP-ManPP, thus indicating that the C-6 hydroxy group of the Manp-1P substrate is not required for binding to the enzyme. When taken into consideration with other previously published work, it appears that this enzyme has potential utility for the chemoenzymatic synthesis of GDP-Manp analogues, which are useful probes for studying enzymes that employ this sugar nucleotide as a substrate.

Carbohydrate-Based Chiral Iodoarene Catalysts: A Survey through the Development of an Improved Catalyst Design

“…25 : Prepared from 22 (5.91 g, 30.0 mmol) accordingly to general procedure E; colorless solid; 71% (9.30 g) yield after column chromatography (PE/EtOAc, 1/2); analytical data were in good accordance with literature values [29].…”

Deoxy sugars. General methods for carbohydrate deoxygenation and glycosidation

“…By subsequent phosphorylation and deprotection, compound 20 was obtained (Scheme 5). 28 Catalytic hydrogenation of an iodide precursor was also used for the synthesis α-GalCer analogues. 29…”

Chemical Biology Tools for Modulating and Visualizing Gram-Negative Bacterial Surface Polysaccharides

“…112 Thorson and colleagues have utilized protein engineering strategies, such as directed evolution, to expand the tolerance of RmlA for structurally diverse NTP and sugar-1-phosphate substrates to produce chemical libraries of NDP-sugars, such as dTDP-β-L-fucose (dTDP-β-L-Fuc), UDP-galactose (UDP-Gal), and dTDPmannose (dTDP-Man), as well as unnatural NDP-sugars. 67,[109][110][111]113 The application of these nucleotide sugar libraries as substrates for the "glycorandomization" of natural products has been reviewed in detail elsewhere. 43 Recently, researchers have taken advantage of the substrate promiscuity exhibited by another bacterial nucleotidyltransferase, Man-1-phosphate guanylyltransferase (ManC), to produce inhibitors of bacterial polysaccharide biosynthetic enzymes.…”