Fructose 1,6-bisphosphate, also known as Harden-Young ester, is
fructose sugar
phosphorylated
In chemistry, phosphorylation is the attachment of a phosphate group to a molecule or an ion. This process and its inverse, dephosphorylation, are common in biology and could be driven by natural selection. Text was copied from this source, wh ...
on carbons 1 and 6 (i.e., is a
fructosephosphate). The β-
D-form of this compound is common in
cells. Upon entering the cell, most
glucose
Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, u ...
and fructose is converted to fructose 1,6-bisphosphate.
In glycolysis
Fructose 1,6-bisphosphate lies within the
glycolysis metabolic pathway
In biochemistry, a metabolic pathway is a linked series of chemical reactions occurring within a cell. The reactants, products, and intermediates of an enzymatic reaction are known as metabolites, which are modified by a sequence of chemical reac ...
and is produced by phosphorylation of
fructose 6-phosphate
Fructose 6-phosphate (sometimes called the Neuberg ester) is a derivative of fructose, which has been phosphorylated at the 6-hydroxy group. It is one of several possible fructosephosphates. The β-D-form of this compound is very common in cells. ...
. It is, in turn, broken down into two compounds:
glyceraldehyde 3-phosphate
Glyceraldehyde 3-phosphate, also known as triose phosphate or 3-phosphoglyceraldehyde and abbreviated as G3P, GA3P, GADP, GAP, TP, GALP or PGAL, is a metabolite that occurs as an intermediate in several central pathways of all organisms.Nelson, D ...
and
dihydroxyacetone phosphate
Dihydroxyacetone phosphate (DHAP, also glycerone phosphate in older texts) is the anion with the formula HOCH2C(O)CH2OPO32-. This anion is involved in many metabolic pathways, including the Calvin cycle in plants and glycolysis.Nelson, D. L.; Co ...
. It is an
allosteric activator of
pyruvate kinase
Pyruvate kinase is the enzyme involved in the last step of glycolysis. It catalyzes the transfer of a phosphate group from phosphoenolpyruvate (PEP) to adenosine diphosphate (ADP), yielding one molecule of pyruvate and one molecule of ATP. P ...
through distinct interactions of binding and allostery at the enzyme's catalytic site
''The numbering of the carbon atoms indicates the fate of the carbons according to their position in fructose 6-phosphate.''
Isomerism
Fructose 1,6-bisphosphate has only one biologically active
isomer, the β-
D-form. There are many other isomers, analogous to those of fructose.
Iron chelation
Fructose 1,6-bis(phosphate) has also been implicated in the ability to bind and sequester Fe(II), a soluble form of iron whose oxidation to the insoluble Fe(III) is capable of generating reactive oxygen species via
Fenton chemistry. The ability of fructose 1,6-bis(phosphate) to bind Fe(II) may prevent such electron transfers, and thus act as an antioxidant within the body. Certain neurodegenerative diseases, like
Alzheimer's and
Parkinson's
Parkinson's disease (PD), or simply Parkinson's, is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms usually emerge slowly, and as the disease worsens, non-motor symptoms becom ...
, have been linked to metal deposits with high iron content, although it is uncertain whether Fenton chemistry plays a substantial role in these diseases, or whether fructose 1,6-bis(phosphate) is capable of mitigating those effects.
See also
*
Fructose 2,6-bisphosphate
Fructose 2,6-bisphosphate, abbreviated Fru-2,6-''P''2, is a metabolite that allosterically affects the activity of the enzymes phosphofructokinase 1 (PFK-1) and fructose 1,6-bisphosphatase (FBPase-1) to regulate glycolysis and gluconeogenesis. F ...
References
External links
*
{{DEFAULTSORT:Fructosebisphosphate16
Monosaccharide derivatives
Organophosphates
Glycolysis