Mannose


Mannose
Mannose
Identifiers
CAS number 31103-86-3 YesY
PubChem 18950
UNII PHA4727WTP N
MeSH Mannose
ChEMBL CHEMBL469448 N
Properties
Molecular formula C6H12O6
Molar mass 180.156 g mol-1
 N (verify) (what is: YesY/N?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references
D and L straight-chain forms of mannose drawn using Fischer projections.

Mannose is a sugar monomer of the aldohexose series of carbohydrates. Mannose is a C-2 epimer of glucose. It is not part of human metabolism, but is a component of microbial cell walls, and is therefore a target of the immune system and also of antibiotics.


Contents

Structure

Two of the cyclic mannose isomers possess a pyranose (six-membered) ring, while the other two possess a furanose (five-membered) ring.

D-Mannose isomers
Skeletal formula Haworth projection
D-Mannose Keilstrich.svg Alpha-D-Mannofuranose.svg
α-D-Mannofuranose
<1 %
Beta-D-Mannofuranose.svg
β-D-Mannofuranose
<1 %
Alpha-D-Mannopyranose.svg
α-D-Mannopyranose
67 %
Beta-D-Mannopyranose.svg
β-D-Mannopyranose
33 %

Metabolism

Mannose is not well metabolized in humans.[1] Therefore, it does not significantly enter the carbohydrate metabolism when taken orally, and although traces of exogeneously introduced mannose have been detected in all body tissues, using radioactive markers, in a well hydrated mammal, 90% of mannose ingested is excreted unconverted into the urine within 30 – 60 minutes, with 99% of the remainder being excreted within the following 8 hours. There is no significant increase in blood-glucose levels during this time.

Mannose is present in numerous glycoconjugates including N-linked glycosylation of proteins. C-mannosylation is also abundant and can be found in collagen-like regions. Mannose is a C-2 epimer of glucose and displays a 4C1 pucker in the solution ring form.

Recombinant proteins produced in yeast may be subject to mannose addition in patterns different from those used by mammalian cells.[2] This difference in recombinant proteins from those normally produced in mammalian organisms may influence the effectiveness of vaccines.

Formation

Mannose can be formed by the oxidation of mannitol.

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

D-mannose is sold as a naturopathic remedy for urinary tract infections, and it is claimed to work through the disruption of adherence of bacteria in the urinary tract.

Etymology

The root of both "mannose" and "mannitol" 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.

Configuration

Mannose differs from glucose by inversion of the C-2 chiral center. This apparently simple change leads to the drastically different chemistry of the two hexoses, as it does the remaining six aldohexoses.

See also

References

  1. ^ Direct utilization of mannose for mammalian glycoprotein biosynthesis. Oxford Journals, Life Sciences, Glycobiology, Volume 8, Number 3 Pp. 285-295.
  2. ^ Vlahopoulos S, Gritzapis AD, Perez SA, Cacoullos N, Papamichail M, Baxevanis CN. Mannose addition by yeast Pichia Pastoris on recombinant HER-2 protein inhibits recognition by the monoclonal antibody herceptin. Vaccine. 2009 Jul 23;27(34):4704-8. Epub 2009 Jun 9.PMID: 19520203.

External links

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Look at other dictionaries:

  • Mannose — Général Nom IUPAC (3S,4S,5S,6R) 6 (hydroxyméthyl) oxane 2,3,4,5 tétrol Synonymes …   Wikipédia en Français

  • mannose — [ manoz ] n. m. • 1902; all. Mannose (1888), abrév. de Mannitose;cf. mannite (→ mannitol) et 1. ose ♦ Biochim. Sucre naturel contenu dans de nombreuses baies et graines. Le mannose est un isomère du fructose et du glucose. ● mannose nom masculin… …   Encyclopédie Universelle

  • Mannōse — (Seminose) C6H12O6 oder CHO(CH.OH)4.CH2.OH, der Aldehyd des Mannits, entsteht neben Fruchtzucker bei vorsichtiger Oxydation des Mannits, aus der Reservezellulose vieler Samen, wie der Steinnuß, beim Kochen mit verdünnter Schwefelsäure, ferner aus …   Meyers Großes Konversations-Lexikon

  • Mannose — Mannose, eine Aldose, die durch Oxydation von Mannit (s.d.) entsteht. Bei fortschreitender Oxydation bilden sich Mannonsäure und Mannozuckersäure. Die Mannonsäure ist ein wichtiges Zwischenprodukt bei der Synthese der Glukose (Traubenzucker). S.a …   Lexikon der gesamten Technik

  • Mannose — Mannōse, s. Mannit …   Kleines Konversations-Lexikon

  • mannose — [man′ōs΄] n. [< MANNITOL + OSE2] a monosaccharide found in some plants and produced by the oxidation of mannitol …   English World dictionary

  • Mannose — Strukturformel Fischer Projektion, offenkettige Darstellung Allgemeines Name …   Deutsch Wikipedia

  • Mannose — Man|no|se 〈f. 19; unz.; Biochem.〉 in Orangenschalen vorkommender Zucker [→ Manna] * * * Man|no|se, hier D Mannose [griech. mánna = Manna (hebräisch man = Geschenk), beim Zug der Israeliten durch die Wüste vom Himmel herabfallende essbare, süß… …   Universal-Lexikon

  • mannose — (= D mannose) Hexose identical to D glucose except that the orientation of the H and OH on carbon 2 are interchanged (ie. the 2 epimer of glucose). Found as constituent of polysaccharides and glycoproteins …   Dictionary of molecular biology

  • mannose — man•nose [[t]ˈmæn oʊs[/t]] n. chem. a hexose, C6H12O6, obtained from the hydrolysis of the ivory nut and yielding mannitol upon reduction • Etymology: < G Mannose, from Mannitose=Mannite (see mannitol) + ose ose II …   From formal English to slang