Heptose phosphate

These are most readily understood when presented in the form of a carbon flow sheet as in Figure 2.10. At one stage a heptose phosphate (sedoheptulose-7-phos-... 

Sedoheptulose 7-phosphate was found to be converted to dehydroshikimic acid about as well as various phosphorylated hexoses. When the heptose phosphate was incubated together with fructose 1,6-diphosphate the degree of conversion was doubled. This led to the suggestion that a reaction product, sedoheptulose 1,7-diphosphate might be the more direct substrate. Test of sedoheptulose 1,7-diphosphate yielded a very high conversion to dehydroshiki c acid (20%). When DPN was added to this, the degree of conversion was almost quantitative (80 %). Since the synthesis of dehydroshikimic acid from sedoheptulose diphosphate involves the removal of two hydrogens as well as two molecules of water, participation of a pyridine nucleotide is understandable. 

In recent years the biosynthetic route for the ADP-heptose precursor of the lipopolysaccharide inner core component in the gram-negative pro-teobacterium E. coli has been elucidated.This involves isomerizion of D- erfo-heptulose-7-phosphate to D-alpha,beta-D-heptose-7-phosphate by GmhA, phosphorylation to D-alpha-D-heptose-1,7-diphosphate by HddA,... 

Formation of a possible precursor of 9, namely, o-glycero-D-manno-heptose 7-phosphate, from D-sedoheptulose 7-phosphate was demonstrated in Salmonella typhimurium.238... 

Fig. 6. Structures of the LPS-derived oligosaccharides and OPS containing legionaminic acid (Leg). [D-a-D-Hep and L-a-D-Hep, D-glycero- and L-glycero-a-D-manno-heptose Kdo, 3-deoxy-D-manno-oct-2-ulosonic acid Fuc4NR3Hb, 4-[(R)-3-hydroxybutanamido]-4,6-dideoxygalactose Ala, L-alanyl Cm, carbamoyl PEtn, ethanolamine phosphate R is acetyl in some repeating units and (S)-3-hydroxybutanoyl in the others.]...

De Castro, C., Molinaro, A., Nunziata, R., Lanzetta, R., Parrilli, M., Holst, O. A novel core region, lacking heptose and phosphate, of the lipopolysaccharide from the Gram-negative bacterium Pseudomonas cichorii (Pseudomonadaceae RNA group I). Eur 1 Org Chem 11 (2004) 2427-2435. 

Heptoses, chromatography of, 287-289 from bacterial polysaccharide, 302 in bacteria, 286, 287 methylated, 288 periodate oxidation of, 288, 289 —> n-glyeero-D-galacto-, 320 —, v-glycero-D-manno-, 288, 320 —, D-glycero-L-numno-, 287, 319, 320, 326 —, h-glycero-v-manno-, 277, 278, 310, 320 Heptulose, D-altro-, 286 1,7-diphosphate, 240-248, 255 7-phosphate, 241-245, 247 —, o-manno 286 Heptulosonic acid, 3-deoxy-, 251 —, 3-deoxy-D-am5t o-, determination of, 252... 

A non-specific bacterial acid phosphatase from Shigella flexneri (PhoN-Sf) has been screened for regioselective phosphorylation of primary alcohol(s) of more than 20 different cyclic and acyclic monosaccharides using pyrophosphate as the phosphate donor (O Scheme 61) [368]. These studies have shown that PhoN-Sf is capable of phosphorylating a range of hexoses (D-glucose epimers, glycosides, and C-2 derivatives), pentoses, heptoses, ketoses, and acyclic carbohydrates. 

Despite the fact that many heptoses are by far less prominent in Nature than hexoses these monosaccharides are found both as metabolic intermediates, and as structural carbohydrates of bacterial cell walls.D-Sedoheptulose 7-phosphate is an important intermediate of the pentose cycle, and D-sedoheptulose 1,7-bisphosphate is present in plants as an intermediate of the dark phase of photosynthetic reactions. L-Glycero-D-manno-heptose was isolated from the oligosaccharides obtained by partial acid hydrolysis of the lipopolysaccharide from Escherichia coli K-12 strain W3100 [153] and Haemophilus influenzae [154]. Both L-glycero-D-wtanno-heptose and D-glycero-D-ma o-heptose were isolated from the lipopolysaccharide of Vibrio parahaemolyticus [155]. 

The tetraglycosyl phosphate repeating-unit polymer of the extracellular polysaccharide of Campylobacter lari strain ATCC 3521 contains 6-deoxy-L-gM/o-heptose (55) in a-pyranosyl form. The identity of this constituent was established by comparison with synthetic 6-deoxy-L-gn/oheptose, with substantiation of the L-enantiomeric configuration through formation of chiral glycosides.259... 

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