Glucose-1-phosphate metabolism (WP260)

Glycogen, a branched polymer of glucose, is a storage molecule whose accumulation is under rigorous control in many cells. In Saccharomyces cerevisiae, glycogen biosynthesis involves three processes: nucleation, elongation, and branching (also known as ramification). The formation of glycogen begins when either Glg1p or Glg2p uses UDP-glucose to self-glucosylate to produce a short alpha (1,4)-glucosyl chain covalently attached to one of their internal tyrosine residues. After the self-glucosylation of Glg1p or Glg2p, glycogen synthase is able to extend the linear alpha (1,4)-glucosyl chains of glycogen by catalyzing the formation of alpha (1,4)-glucosidic bonds from UDP- glucose at the non-reducing ends. Branches can be added into the glycogen molecule by Glc3p, which is the glycogen branching enzyme (EC: in S. cerevisiae.
last edited


J.Heckman, MaintBot, Christine Chichester, Egonw, DeSl, and Mkutmon

Cited In


Saccharomyces cerevisiae



Pathway Ontology: glycogen biosynthetic pathway glucose utilization pathway glucose conversion pathway


Label Type Compact Identifier
UTP Metabolite chebi:46398
UDP-D-glucose Metabolite chebi:46229
H2O Metabolite chebi:15377
NADP Metabolite chebi:44409
beta-D-Glucose Metabolite chebi:15903
delta-Glucono-delta-lactone Metabolite chebi:16217
glucose-1-phosphate Metabolite chebi:16077
Glycogen Metabolite chebi:28087
YHL012W GeneProduct sgd:S000001004
pyrophosphate Metabolite cas:2466-09-3
(1,4-alpha-D-glucosyl)n - R Metabolite chebi:15444
a glucosylated glycogenin Metabolite None
fructose Metabolite cas:7776-48-9
glucose-6-phosphate Metabolite chebi:75150
PGM1 GeneProduct sgd:S000001610
GSY2 GeneProduct ensembl:YLR258W
UDP Metabolite chebi:17659
UDP-D-glucose Metabolite chebi:46229
UGP1 GeneProduct sgd:S000001518
GSY1 GeneProduct ensembl:YFR015C
NADPH Metabolite cas:53-57-6
phosphate Metabolite cas:14265-44-2
PGM2 GeneProduct sgd:S000004711
GLC3 GeneProduct ensembl:YEL011W
(1,4-alpha-D-Glucosyl)n+1 - R Metabolite chebi:28102
UDP-D-glucose Metabolite chebi:46229
UDP Metabolite chebi:17659
UDP-D-glucose Metabolite chebi:46229
UDP Metabolite chebi:17659


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