|Superclasses:||Reactions Classified By Conversion Type → Simple Reactions → Chemical Reactions|
|Reactions Classified By Substrate → Small-Molecule Reactions|
EC Number: 18.104.22.1688
In Pathway: dolichyl-diphosphooligosaccharide biosynthesis
Supersedes EC number: 22.214.171.124
The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.
Most BioCyc compounds have been protonated to a reference pH value of 7.3, and some reactions have been computationally balanced for hydrogen by adding free protons. Please see the PGDB Concepts Guide for more information.
Mass balance status: Balanced.
Enzyme Commission Primary Name: dolichyl-P-Man:Man5GlcNAc2-PP-dolichol α-1,3-mannosyltransferase
Enzyme Commission Synonyms: Man5GlcNAc2-PP-Dol mannosyltransferase, ALG3, dolichyl-P-Man:Man(5)GlcNAc(2)-PP-dolichyl mannosyltransferase, Not56-like protein, Alg3 α-1,3-mannosyl transferase, Dol-P-Man:Man5GlcNAc2-PP-Dol α-1,3-mannosyltransferase
Standard Gibbs Free Energy (ΔrG'° in kcal/mol): 7.52124 [Latendresse13]
Enzyme Commission Summary:
The formation of N-glycosidic linkages of glycoproteins involves the ordered assembly of the common Glc3Man9GlcNAc2 core-oligosaccharide on the lipid carrier dolichyl diphosphate. Early mannosylation steps occur on the cytoplasmic side of the endoplasmic reticulum with GDP-Man as donor, the final reactions from a (mannosyl)5-(N-acetylglucosaminyl)2-diphosphodolichol to a (mannosyl)9-(N-acetylglucosaminyl)2-diphosphodolichol on the lumenal side use dolichyl β-D-mannosyl phosphate. The first step of this assembly pathway on the luminal side of the endoplasmic reticulum is catalysed by ALG3.
Unification Links: Rhea:29530
Cipollo00: Cipollo JF, Trimble RB (2000). "The accumulation of Man(6)GlcNAc(2)-PP-dolichol in the Saccharomyces cerevisiae Deltaalg9 mutant reveals a regulatory role for the Alg3p alpha1,3-Man middle-arm addition in downstream oligosaccharide-lipid and glycoprotein glycan processing." J Biol Chem 275(6);4267-77. PMID: 10660594
Sharma01: Sharma CB, Knauer R, Lehle L (2001). "Biosynthesis of lipid-linked oligosaccharides in yeast: the ALG3 gene encodes the Dol-P-Man:Man5GlcNAc2-PP-Dol mannosyltransferase." Biol Chem 382(2);321-8. PMID: 11308030
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