Reaction: Addition of the first mannose to the N-glycan precursor by ALG1
- in pathway: Biosynthesis of the N-glycan precursor (dolichol lipid-linked oligosaccharide, LLO) and transfer to a nascent protein
A mannose is added to the N-glycan precursor via a beta-1,4 linkage. The reaction is catalyzed by ALG1 (Takahashi T et al, 2000). Defects in ALG1 lead to congenital disorder of glycosylation type 1K (CDG1K) (Schwarz et al. 2004; Kranz et al. 2004; Grubenmann et al. 2004).
Reaction - small molecule participants:
GDP [cytosol]
MDCDD [integral component of cytoplasmic side of endoplasmic reticulum membrane]
GDP-Man [cytosol]
N,N'-DCDOLDP [integral component of cytoplasmic side of endoplasmic reticulum membrane]
Reactome.org reaction link: R-HSA-446218
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Reaction input - small molecules:
GDP-alpha-D-mannose(2-)
diacetylchitobiosyldiphosphodolichol
Reaction output - small molecules:
GDP(3-)
beta-D-mannosyldiacetylchitobiosyldiphosphodolichol
Reactome.org link: R-HSA-446218