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MetaCyc Pathway: trehalose degradation I (low osmolarity)
Traceable author statement to experimental supportInferred from experiment

Enzyme View:

Pathway diagram: trehalose degradation I (low osmolarity)

This view shows enzymes only for those organisms listed below, in the list of taxa known to possess the pathway. If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.

Superclasses: Degradation/Utilization/AssimilationCarbohydrates DegradationSugars DegradationTrehalose Degradation

Some taxa known to possess this pathway include : Bacillus subtilis, Escherichia coli K-12 substr. MG1655, Paenibacillus popilliae

Expected Taxonomic Range: Bacteria

There are several alternative pathways for the degradation of trehalose. Depending on the organism, trehalose may enter the cell either through a permease, in which case it remains unmodified, or it may be transported by a phosphotransferase system (PTS), resulting in the phoshorylated trehalose-6-phosphate form. Degradation then proceeds by different mechanisms: Unmodified trehalose may be degraded by a hydrolyzing trehalase (see trehalose degradation II (trehalase)), or it may be split by the action of a trehalose phosphorylase (see trehalose degradation IV and trehalose degradation V). Likewise, trehalose-6-phosphate may be either hydrolyzed by trehalose-6-phosphate hydrolase (see trehalose degradation I (low osmolarity)) or it could be attacked by a trehalose-6-phosphate phosphorylase (see trehalose degradation III).

Trehalose degradation utilizing a trehalose-6-phosphate is found in many bacteria. It was studied extensively in the Gram-negative bacterium Escherichia coli (under conditions of low osmolarity). However, it has also been demonstrated in some Gram-positive bacteria, including Paenibacillus popilliae and Bacillus subtilis [Bhumiratana74, Helfert95].

While Escherichia coli only synthesizes trehalose under conditions of high osmolarity, it can degrade the sugar under conditions of both low and high osmolarity. In fact, Escherichia coli can grow with trehalose as the sole carbon source. Different pathways are employed under different osmolarity conditions.

Since no trehalose biosynthesis is happening in low osmolarity conditions, the only source of trehalose is external supply. Trehalose is imported into the cell by a PTS system for trehalose, which is composed of the EIIAGlc of the glucose-PTS, and a trehalose-specific EIITre, encoded by the treB gene. Trehalose is phosphorylated during the transport and enters the cytoplasm as trehalose-6-phosphate.

The resulting trehalose-6-phosphate is then hydrolyzed by trehalose-6-phosphate hydrolase, which is encoded by the treC gene, yielding glucose and glucose-6-phosphate. The free glucose is phosphorylated further by glucokinase into a second molecule of glucose-6-phosphate, and both glucose-6-phosphate moieties enter glycolysis [Klein95, Rimmele94].

Variants: trehalose degradation II (trehalase), trehalose degradation III, trehalose degradation IV, trehalose degradation V, trehalose degradation VI (periplasmic)

Unification Links: EcoCyc:TREDEGLOW-PWY

Created 08-Oct-1996 by Riley M, Marine Biological Laboratory
Revised 10-Mar-2005 by Caspi R, SRI International


Bhumiratana74: Bhumiratana A, Anderson RL, Costilow RN (1974). "Trehalose metabolism by Bacillus popilliae." J Bacteriol 119(2);484-93. PMID: 4369400

Helfert95: Helfert C, Gotsche S, Dahl MK (1995). "Cleavage of trehalose-phosphate in Bacillus subtilis is catalysed by a phospho-alpha-(1-1)-glucosidase encoded by the treA gene." Mol Microbiol 16(1);111-120. PMID: 7651129

Klein95: Klein W, Horlacher R, Boos W (1995). "Molecular analysis of treB encoding the Escherichia coli enzyme II specific for trehalose." J Bacteriol 177(14);4043-52. PMID: 7608078

Rimmele94: Rimmele M, Boos W (1994). "Trehalose-6-phosphate hydrolase of Escherichia coli." J Bacteriol 1994;176(18);5654-64. PMID: 8083158

Other References Related to Enzymes, Genes, Subpathways, and Substrates of this Pathway

Alajmo90: Alajmo E, de Meester W, Polli G (1990). "Facial nerve involvement: macroscopic and clinical evidence, therapeutic approach." Acta Otorhinolaryngol Ital 10 Suppl 29;35-42. PMID: 2177945

Albig88: Albig W, Entian KD (1988). "Structure of yeast glucokinase, a strongly diverged specific aldo-hexose-phosphorylating isoenzyme." Gene 73(1);141-52. PMID: 3072253

Arora95: Arora KK, Pedersen PL (1995). "Glucokinase of Escherichia coli: induction in response to the stress of overexpressing foreign proteins." Arch Biochem Biophys 1995;319(2);574-8. PMID: 7786044

Asensio58: Asensio C, Sols A (1958). "Utilization and phosphorylation of sugars by Escherichia coli." Rev Esp Fisiol 14(4);269-75. PMID: 13658662

Asensio63: Asensio C, Avigad G, Horecker BL (1963). "Preferential galactose utilization in a mutant strain of E. coli." Arch Biochem Biophys 103;299-309. PMID: 14103281

Boos90: Boos W, Ehmann U, Forkl H, Klein W, Rimmele M, Postma P (1990). "Trehalose transport and metabolism in Escherichia coli." J Bacteriol 172(6);3450-61. PMID: 2160944

Curtis75: Curtis SJ, Epstein W (1975). "Phosphorylation of D-glucose in Escherichia coli mutants defective in glucosephosphotransferase, mannosephosphotransferase, and glucokinase." J Bacteriol 122(3);1189-99. PMID: 1097393

Dai99: Dai N, Schaffer A, Petreikov M, Shahak Y, Giller Y, Ratner K, Levine A, Granot D (1999). "Overexpression of Arabidopsis hexokinase in tomato plants inhibits growth, reduces photosynthesis, and induces rapid senescence." Plant Cell 11(7);1253-66. PMID: 10402427

Decker99: Decker K, Gerhardt F, Boos W (1999). "The role of the trehalose system in regulating the maltose regulon of Escherichia coli." Mol Microbiol 32(4);777-88. PMID: 10361281

DiazMejia09: Diaz-Mejia JJ, Babu M, Emili A (2009). "Computational and experimental approaches to chart the Escherichia coli cell-envelope-associated proteome and interactome." FEMS Microbiol Rev 33(1);66-97. PMID: 19054114


Fukuda83: Fukuda Y, Yamaguchi S, Shimosaka M, Murata K, Kimura A (1983). "Cloning of the glucokinase gene in Escherichia coli B." J Bacteriol 156(2);922-5. PMID: 6313627

Giese05: Giese JO, Herbers K, Hoffmann M, Klosgen RB, Sonnewald U (2005). "Isolation and functional characterization of a novel plastidic hexokinase from Nicotiana tabacum." FEBS Lett 579(3);827-31. PMID: 15670855

GOA01: GOA, MGI (2001). "Gene Ontology annotation based on Enzyme Commission mapping." Genomics 74;121-128.

GOA01a: GOA, DDB, FB, MGI, ZFIN (2001). "Gene Ontology annotation through association of InterPro records with GO terms."

GOA06: GOA, SIB (2006). "Electronic Gene Ontology annotations created by transferring manual GO annotations between orthologous microbial proteins."

Gotsche95: Gotsche S, Dahl MK (1995). "Purification and characterization of the phospho-alpha(1,1)glucosidase (TreA) of Bacillus subtilis 168." J Bacteriol 177(10);2721-6. PMID: 7751281

Hansen03: Hansen T, Schonheit P (2003). "ATP-dependent glucokinase from the hyperthermophilic bacterium Thermotoga maritima represents an extremely thermophilic ROK glucokinase with high substrate specificity." FEMS Microbiol Lett 226(2);405-11. PMID: 14553940

HernandezMontal03: Hernandez-Montalvo V, Martinez A, Hernandez-Chavez G, Bolivar F, Valle F, Gosset G (2003). "Expression of galP and glk in a Escherichia coli PTS mutant restores glucose transport and increases glycolytic flux to fermentation products." Biotechnol Bioeng 83(6);687-94. PMID: 12889033

Ishihama08: Ishihama Y, Schmidt T, Rappsilber J, Mann M, Hartl FU, Kerner MJ, Frishman D (2008). "Protein abundance profiling of the Escherichia coli cytosol." BMC Genomics 9;102. PMID: 18304323

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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 Tue May 3, 2016, biocyc14.