guanosine-diphosphate and mannuronic-acid

Topics: Alginates; Carbohydrate Dehydrogenases; Chemistry Techniques, Synthetic; Guanosine Diphosphate; Hexuronic Acids; Pseudomonas aeruginosa; Recombinant Proteins

Described is the first synthesis of guanosine diphosphate mannuronic acid (GDP-ManA), the sugar donor used by algae and bacteria for the production of alginate, an anionic polysaccharide composed of β-d-mannuronic acid (ManA) and α-l-guluronic acid (GulA). Understanding the biosynthesis of these polyanionic polysaccharides on the molecular level, opens up avenues to use and modulate the biosynthesis machinery for biotechnological and therapeutic applications. The synthesis reported here delivers multi-milligram amounts of the GDP-ManA donor that can be used to study the polymerase (Alg8 in Pseudomonas aeruginosa) that generates the poly-ManA chain. Also reported is the assembly of two close analogues of GDP-ManA: the first bears a C-4-O-methyl group, while the second has been deoxygenated at this position. Both molecules may be used as "chain stoppers" in future enzymatic ManA polymerisation reactions. The crucial pyrophosphate linkage of the GDP-mannuronic acids has been constructed by the phosphorylation of the appropriate ManA-1-phosphates with a guanosine phosphoramidite.

Topics: Chemistry Techniques, Synthetic; Guanosine Diphosphate; Hexuronic Acids

Topics: Chromatography; Electrophoresis; Eukaryota; Fucus; Guanine Nucleotides; Guanosine Diphosphate; Hexuronic Acids; Research; Ultraviolet Rays; Uronic Acids