Mannose-1-phosphate

Structural formula
	α- anomer of D- mannose-1-phosphate ( pyranose form )
General
Surname	Mannose-1-phosphate
other names	M1P
Molecular formula	C 6 H 13 O 9 P
External identifiers / databases
PubChem	644175
DrugBank	DB02867
Wikidata	Q258734
properties
Molar mass	290.16 g mol −1
safety instructions
GHS labeling of hazardous substances	no GHS pictograms
	no GHS pictograms
H and P phrases	H: no H-phrases
	P: no P-phrases
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Mannose-1-phosphate is a phosphoric acid ester of mannose and the isomer of mannose-6-phosphate . It is an intermediate in the provision of mannose for glycosylation of proteins and lipids . Physiologically, only the D isomer plays a role.

meaning

Mannose-1-phosphate is used for the synthesis of GDP-mannose (or dolicholmonophosphate mannose , Dol-P-Man), which in turn is used as "activated" mannose for the synthesis of a large number of polysaccharides (for example xanthan gum ), GPI anchors and glycans. In the latter, a so-called mannosylation takes place on proteins ( O- mannosylation), i.e. the attachment of mannose to threonine or serine residues ( glycosylation ). C-mannosylated proteins also require GDP-mannose.

In addition, the “activated” L - fucose ( GDP-fucose ) is formed from GDP-mannose .

Mannose-1-phosphate cannot pass through cell membranes and it is not transported into the cell.

Reactions

The enzyme phosphomannomutase provides α- D- mannose-1-phosphate from D- mannose-6-phosphate.

α- D- mannose-1-phosphate itself serves to provide GDP-mannose, which either catalyzes a GTP-dependent mannose-1-phosphate guanylyl transferase ( EC 2.7.7.13 ) with consumption of GTP :

{\ displaystyle {\ text {Mannose-1-phosphate}} + {\ text {GTP}} \ longrightarrow {\ text {GDP-Mannose}} + {\ text {PP}} _ {i}}

Alternatively, a GDP -dependent mannose-1-phosphate-guanylyltransferase ( EC 2.7.7.22 ) can also form GDP-mannose, according to:

{\ displaystyle {\ text {Mannose-1-phosphate}} + {\ text {GDP}} \ longrightarrow {\ text {GDP-Mannose}} + {\ text {P}} _ {i}}

pathology

A mutation of phosphomannomutase (PMM-2) leads to a defect, so that sufficient mannose-1-phosphate can no longer be provided. This manifests itself in the fact that many proteins can no longer be modified and leads to a serious disease, the Congenital Disorder of Glycosylation of type 1a (CDG-1a).

literature

HH Freeze: Towards a therapy for phosphomannomutase 2 deficiency, the defect in CDG-Ia patients. In: Biochim Biophys Acta . 1792, No. 9, 2009, pp. 835-840, PMID 19339218 , PMC 2783247 (free full text) (Eng.).

Web links

Wikibooks: Biochemistry and Pathobiochemistry: Fructose, Mannose and Fucose Metabolism - Learning and Teaching Materials

Individual evidence

↑ Data sheet α-D (+) Mannose 1-phosphate sodium salt hydrate from Sigma-Aldrich , accessed on May 22, 2017 ( PDF ).
↑ Huan Zhou, Lihua Sun, Jian Li, Chunyan Xu, Feng Yu, Yahui Liu, Chaoneng Ji, Jianhua He: The crystal structure of human GDP-l-fucose synthase . In: Acta Biochimica et Biophysica Sinica . tape 45 , no. 9 , January 9, 2013, p. 720-725 , doi : 10.1093 / abbs / gmt066 , PMID 23774504 ( oxfordjournals.org [PDF]).

[Sigma-1] Data sheet α-D (+) Mannose 1-phosphate sodium salt hydrate from Sigma-Aldrich , accessed on May 22, 2017 ( PDF ).

[2] Huan Zhou, Lihua Sun, Jian Li, Chunyan Xu, Feng Yu, Yahui Liu, Chaoneng Ji, Jianhua He: The crystal structure of human GDP-l-fucose synthase . In: Acta Biochimica et Biophysica Sinica . tape 45 , no. 9 , January 9, 2013, p. 720-725 , doi : 10.1093 / abbs / gmt066 , PMID 23774504 ( oxfordjournals.org [PDF]).