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mannose: Definition and Much More from Answers.com

️Wed Jul 01 2015

Mannose

Identifiers
CAS number	31103-86-3
PubChem	18950
MeSH	Mannose
Properties
Molecular formula	C₆H₁₂O₆
Molar mass	180.156
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

D and L forms

Mannose is a sugar monomer of the hexose series of carbohydrates.

Metabolism

Mannose enters the carbohydrate metabolism stream in two steps:

First it undergoes phosphorylation to mannose-6-phosphate by hexokinase.
Then, it is converted to fructose-6-phosphate by mannose phosphate isomerase.

Formation

Mannose can be formed by the oxidation of mannitol.

It can also be formed from D-glucose in the Lobry-de Bruyn-van Ekenstein transformation

Etymology

The root of both "mannose" and "manitol" is manna, which the Bible records as the food supplied to the Israelites during their journey through the Sinai Peninsula. Manna is a sweet secretion of several trees and shrubs, such as Fraxinus ornus.

Cranberry juice

D-Mannose, which appears in some fruits including cranberry, has been postulated to prevent the adhesion of bacteria to the epithelium of the urinary tract and Urinary bladder through a mechanism presumed to be competitive in nature with the polysaccharide coating of the cystic epithelium. While no studies have objectively verified this mechanism, anecdotal reports from patients show some improvement in symptoms.^{[citation needed]}

Configuration

The fact that D-mannose has the same configuration at its penultimate carbon as D-glyceraldehyde is unsurprising as that is what defines the dextro classification. However, mannose differs from D-glucose by inversion of the C2 chiral centre. This apparently simple change leads to the drastically different chemistry of the two hexoses, as it does the remaining six hexoses.

References

External links

Major families of biochemicals
Peptides \| Amino acids \| Nucleic acids \| Carbohydrates \| Lipids \| Terpenes \| Carotenoids \| Tetrapyrroles \| Enzyme cofactors \| Steroids \| Flavonoids \| Alkaloids \| Polyketides \| Glycosides
Analogues of nucleic acids:	Types of Carbohydrates	Analogues of nucleic acids:
General:	Aldose \| Ketose \| Pyranose \| Furanose
Geometry:	Triose \| Tetrose \| Pentose \| Hexose \| Heptose \| Cyclohexane conformation \| Anomer \| Mutarotation
Small/Large:	Glyceraldehyde \| Dihydroxyacetone \| Erythrose \| Threose \| Erythrulose \| Sedoheptulose
Trioses:	ketotriose \| Aldotriose
Tetroses:	Erythrulose \| Erythrose \| Threose
Pentoses:	Arabinose \| Deoxyribose \| Lyxose \| Ribose \| Ribulose \| Xylose \| Xylulose
Hexoses:	Glucose \| Galactose \| Mannose \| Gulose \| Idose \| Talose \| Allose \| Altrose \| Fructose \| Sorbose \| Tagatose \| Psicose \| Fucose \| Rhamnose
Disaccharides:	Sucrose \| Lactose \| Trehalose \| Maltose
Polymers:	Glycogen \| Starch (Amylose \| Amylopectin) \| Cellulose \| Chitin \| Stachyose \| Inulin \| Dextrin
Glycosaminoglycans:	Heparin \| Chondroitin sulfate \| Hyaluronan \| Heparan sulfate \| Dermatan sulfate \| Keratan sulfate
Aminoglycosides:	Kanamycin \| Streptomycin \| Tobramycin \| Neomycin \| Paromomycin \| Apramycin \| Gentamicin \| Netilmicin \| Amikacin

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