Updated BioCyc iOS App now
available in iTunes store
Updated BioCyc iOS App now
available in iTunes store
Updated BioCyc iOS App now
available in iTunes store
Updated BioCyc iOS App now
available in iTunes store
Updated BioCyc iOS App now
available in iTunes store
twitter

MetaCyc Compound Class: maltose

Synonyms: α-D-glucopyranose-(1→4)-D-glucopyranose, maltose

Superclasses: all carbohydratesa carbohydratea glycanan oligosaccharidea disaccharide
all carbohydratesa carbohydratea glycanan oligosaccharidea malto-oligosaccharidea linear malto-oligosaccharide

Summary:
Maltose is composed of two glucose molecules linked by an α 1,4-glycosidic linkage. Maltose is produced by the hydrolysis of starch and similar compounds, and can be hydrolyzed to glucose by the enzyme maltase.

maltose compound structure

Glycan icon:

maltose compound structure

Chemical Formula: C12H22O11

Instances:
α-maltose,
β-maltose

Citations: [Stryer88]

Molecular Weight: 342.3 Daltons

Monoisotopic Molecular Weight: 342.11621154930003 Daltons

SMILES: C(C1(OC(C(C(C1O)O)O)OC2(C(OC(C(C2O)O)O)CO)))O

InChI: InChI=1S/C12H22O11/c13-1-3-5(15)6(16)9(19)12(22-3)23-10-4(2-14)21-11(20)8(18)7(10)17/h3-20H,1-2H2/t3-,4-,5-,6+,7-,8-,9-,10-,11?,12-/m1/s1

InChIKey: InChIKey=GUBGYTABKSRVRQ-PICCSMPSSA-N

Unification Links: CAS:69-79-4, ChEBI:17306, ChemSpider:6019

Standard Gibbs Free Energy of Change Formation (ΔfG in kcal/mol): -150.79538Inferred by computational analysis [Latendresse13]

Reactions known to consume the compound:

glycogen degradation I :
maltotetraose + D-glucopyranose ← maltotriose + maltose

starch degradation I :
maltose + H2O → 2 D-glucopyranose

starch degradation II :
a linear malto-oligosaccharide [(glucose)n] + H2O → a linear malto-oligosaccharide [(glucose)n-2] + maltose

starch degradation V :
a maltodextrin(n+1) + D-glucopyranose ← a maltodextrin(n) + maltose

sucrose biosynthesis II :
SHG-glucosyln+1 + D-glucopyranose ← SHG-glucosyln + maltose

starch degradation I :
a linear malto-oligosaccharide [(glucose)n] + H2O → β-maltose

Reactions known to produce the compound:

glycogen degradation I :
maltotriose + H2O → maltose + D-glucopyranose

starch degradation II :
an exposed unphosphorylated, unbranched malto-oligosaccharide tail on amylopectin[chloroplast stroma] + n H2O[chloroplast stroma]maltose[chloroplast stroma] + an exposed unphosphorylated, (α-1,6)-branched malto-oligosaccharide tail on amylopectin[chloroplast stroma]
an exposed unphosphorylated, unbranched malto-oligosaccharide tail on amylopectin[chloroplast stroma] + n H2O[chloroplast stroma] → amylopectin[chloroplast stroma] + maltose[chloroplast stroma]

starch degradation IV :
a maltodextrin + H2O → maltose + D-glucopyranose

starch degradation V :
starch[extracellular space] + H2O[extracellular space] → a maltodextrin(n)[extracellular space] + maltose[extracellular space] + D-glucopyranose[extracellular space]

Not in pathways:
(1,6-α-D-glucosyl)(m+1) + H2O → (1,6-α-D-glucosyl)(m-1) + maltose
α-maltose 6'-phosphate + H2O → maltose + phosphate
starch + H2O → maltose + glucose

starch degradation I :
starch → a linear malto-oligosaccharide

starch degradation II :
an exposed unphosphorylated, (α-1,6)-branched malto-oligosaccharide tail on amylopectin[chloroplast stroma] + n H2O[chloroplast stroma] → amylopectin[chloroplast stroma] + n a linear malto-oligosaccharide[chloroplast stroma]

Not in pathways:
a long-linear glucan + n H2O → a linear malto-oligosaccharide

starch biosynthesis :
n a (1,6)-α-D-glucosyl-(1,4)-α-glucan highly branched[chloroplast stroma] + n H2O[chloroplast stroma] → n a malto-oligosaccharide[chloroplast stroma] + n (1,6)-α-D-glucosyl-(1,4)-α-glucan moderately branched[chloroplast stroma]

Not in pathways:
keratan sulfate + H2O → n an oligosaccharide
blood group substance B + H2O → n an oligosaccharide
blood group substance A + H2O → n an oligosaccharide
a sialyloligosaccharide + H2O → an oligosaccharide + N-acetylneuraminate
a 1,2-β-D-glucan + H2O → n an oligosaccharide
a fucoidan + H2O → fucose + a fucose sulfate + an oligosaccharide

Reactions known to both consume and produce the compound:

maltose degradation :
maltose + phosphate ↔ β-D-glucose 1-phosphate + D-glucopyranose

trehalose biosynthesis IV :
maltose ↔ α,α-trehalose

In Reactions of unknown directionality:

Not in pathways:
2 α-D-glucopyranose 1-phosphate + H2O = maltose + 2 phosphate
maltopentaose + D-glucopyranose = maltotetraose + maltose
maltohexaose + D-glucopyranose = maltopentaose + maltose
maltohexaose + maltose = maltoheptaose + D-glucopyranose
maltose + acetyl-CoA = 6-O-acetyl-α-D-glucopyranosyl-(1→4)-D-glucose + coenzyme A

Not in pathways:
a linear malto-oligosaccharide [(glucose)n] + phosphate = a linear malto-oligosaccharide [(glucose)n-1] + α-D-glucopyranose 1-phosphate

In Transport reactions:
maltose[chloroplast stroma]maltose[cytosol],
maltose[cco-cytosol-cco-chlor-str]maltose[cco-cytosol-cco-chlor-str],
maltose[extracellular space] + ATP + H2O → maltose[cytosol] + ADP + phosphate + H+,
maltose[extracellular space] + H+[extracellular space]maltose[cytosol] + H+[cytosol],
maltose[extracellular space]maltose[periplasm],
maltose[periplasm] + ATP + H2O → maltose[cytosol] + ADP + phosphate + H+,
maltose[periplasm]maltose[cytosol],
a [PTS enzyme I]-Nπ-phospho-L-histidine + maltose[out] → maltose 6'-phosphate[in] + a [PTS enzyme I]-L-histidine,
an oligosaccharide[extracellular space] + ATP + H2O ↔ an oligosaccharide[cytosol] + ADP + phosphate

Enzymes inhibited by maltose, sorted by the type of inhibition, are:

Inhibitor (Mechanism unknown) of: sucrose transporter [Sauer94], sucrose transporter [Sauer94], UDP-α-D-glucose:glucosyl-glycogenin α-D-glucosyltransferase [Cao93], UDP-α-D-glucose:glycogenin α-D-glucosyltransferase [Cao93]

This compound has been characterized as an alternative substrate of the following enzymes: sucrose 3-dehydrogenase, aldose sugar dehydrogenase, α-1,4-glucan lyase, D-glucose dehydrogenase, maltodextrin glucosidase, kojibiose phosphorylase, isoprimeverose α-xylosidase

Credits:
Created 29-Sep-2012 by Caspi R, SRI International


References

Cao93: Cao Y, Mahrenholz AM, DePaoli-Roach AA, Roach PJ (1993). "Characterization of rabbit skeletal muscle glycogenin. Tyrosine 194 is essential for function." J Biol Chem 268(20);14687-93. PMID: 8325847

Latendresse13: Latendresse M. (2013). "Computing Gibbs Free Energy of Compounds and Reactions in MetaCyc."

Sauer94: Sauer N, Stolz J (1994). "SUC1 and SUC2: two sucrose transporters from Arabidopsis thaliana; expression and characterization in baker's yeast and identification of the histidine-tagged protein." Plant J 6(1);67-77. PMID: 7920705

Stryer88: Stryer L "Biochemistry." WH Freeman and Co., 3rd edition, New York, 1988.

Zeeman10: Zeeman SC, Kossmann J, Smith AM (2010). "Starch: its metabolism, evolution, and biotechnological modification in plants." Annu Rev Plant Biol 61;209-34. PMID: 20192737


Report Errors or Provide Feedback
Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by Pathway Tools version 19.5 (software by SRI International) on Sat Feb 6, 2016, biocyc13.