Glucose 1-phosphate (also called cori ester) is a
glucose molecule with a
phosphate group on the 1'-carbon. It can exist in either the α- or β-
anomer
In carbohydrate chemistry, a pair of anomers () is a pair of near-identical stereoisomers that differ at only the anomeric carbon, the carbon that bears the aldehyde or ketone functional group in the sugar's open-chain form. However, in order fo ...
ic form.
Reactions of α-glucose 1-phosphate
Catabolic
In
glycogenolysis, it is the direct product of the reaction in which
glycogen phosphorylase cleaves off a
molecule of
glucose from a greater
glycogen structure. A deficiency of muscle glycogen phosphorylase is known as
glycogen storage disease type V
Glycogen storage disease type V (GSD5, GSD-V), also known as McArdle's disease, is a metabolic disorder, one of the metabolic myopathies, more specifically a muscle glycogen storage disease, caused by a deficiency of myophosphorylase. Its inci ...
(McArdle Disease).
To be utilized in cellular catabolism it must first be converted to
glucose 6-phosphate
Glucose 6-phosphate (G6P, sometimes called the Robison ester) is a glucose sugar phosphorylated at the hydroxy group on carbon 6. This dianion is very common in cells as the majority of glucose entering a cell will become phosphorylated in this way ...
by the
enzyme phosphoglucomutase in a free equilibrium. One reason that cells form glucose 1-phosphate instead of glucose during glycogen breakdown is that the very polar phosphorylated glucose cannot leave the cell membrane and so is marked for intracellular catabolism.
Phosphoglucomutase-1 deficiency is known as
glycogen storage disease
A glycogen storage disease (GSD, also glycogenosis and dextrinosis) is a metabolic disorder caused by an enzyme deficiency affecting glycogen synthesis, glycogen breakdown, or glucose breakdown, typically in muscles and/or liver cells.
GSD has ...
type 14 (GSD XIV).
Orphanet: Glycogen storage disease due to phosphoglucomutase deficiency
/ref>
Anabolic
In glycogenesis, free glucose 1-phosphate can also react with UTP to form UDP-glucose,UDP-glucose pyrophosphorylase
Uridine diphosphate glucose (uracil-diphosphate glucose, UDP-glucose) is a nucleotide sugar. It is involved in glycosyltransferase reactions in metabolism.
Functions
UDP-glucose is used in nucleotide sugar metabolism as an activated form of glu ...
. It can then return to the greater glycogen structure via glycogen synthase.
β-Glucose 1-phosphate
β-Glucose 1-phosphate is found in some microbes. It is produced by inverting α-glucan phosphorylases including maltose phosphorylase
In enzymology, a maltose phosphorylase () is an enzyme that catalyzes the chemical reaction
:maltose + phosphate \rightleftharpoons D-glucose + beta-D-glucose 1-phosphate
Thus, the two substrates of this enzyme are maltose and phosphate, whereas ...
, kojibiose phosphorylase
In enzymology, a kojibiose phosphorylase () is an enzyme that catalyzes the chemical reaction
:2-alpha-D-glucosyl-D-glucose + phosphate \rightleftharpoons D-glucose + beta-D-glucose 1-phosphate
Thus, the two substrates of this enzyme are kojibi ...
and trehalose phosphorylase and is then converted into glucose 6-phosphate
Glucose 6-phosphate (G6P, sometimes called the Robison ester) is a glucose sugar phosphorylated at the hydroxy group on carbon 6. This dianion is very common in cells as the majority of glucose entering a cell will become phosphorylated in this way ...
by β-phosphoglucomutase.
See also
* Pentose phosphate pathway
The pentose phosphate pathway (also called the phosphogluconate pathway and the hexose monophosphate shunt and the HMP Shunt) is a metabolic pathway parallel to glycolysis. It generates NADPH and pentoses (5-carbon sugars) as well as ribose 5-pho ...
* Gerty Cori
Gerty Theresa Cori (; August 15, 1896 – October 26, 1957) was an Austro-Hungarian and American biochemist who in 1947 was the third woman to win a Nobel Prize in science, and the first woman to be awarded the Nobel Prize in Physiology or Me ...
References
{{Fructose and galactose metabolic intermediates
Organophosphates
Monosaccharide derivatives
Phosphate esters