If an enzyme name is shown in bold, there is experimental evidence for this enzymatic activity.
Locations of Mapped Genes:
|Superclasses:||Degradation/Utilization/Assimilation → Carbohydrates Degradation → Sugars Degradation → Trehalose Degradation|
There are several alternative pathways for the degradation of trehalose. Depending on the organism and the particular environmental conditions, trehalose may be broken down outside of the cytoplasm, 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 phosphorylated trehalose-6-phosphate form. Degradation can proceed by different mechanisms: Unmodified trehalose may be degraded by a hydrolyzing trehalase (see trehalose degradation II (trehalase) and trehalose degradation VI (periplasmic)), 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).
About This Pathway
E. coli can grow with trehalose as the sole carbon source, and employs different pathways for its degradation under different osmolarity conditions. Under conditions of high osmolarity, the PTS pathway for uptake of trehalose (trehalose degradation I (low osmolarity)) is blocked. The periplasmic trehalase (TreA) provides the cell the ability to utilize trehalose under those conditions [Gutierrez89]. External trehalose is hydrolyzed by TreA into two molecules of glucose [Boos87], which are then transported into the cytoplasm through the glucose PTS [Styrvold91]. TreA also has a second function: under high osmotic conditions, the bacterium synthesizes large amounts of trehalose to be used as an osmoprotectant. TreA recycles trehalose molecules that leak from the cytoplasm into the periplasm [Giaever88].
Boos87: Boos W, Ehmann U, Bremer E, Middendorf A, Postma P (1987). "Trehalase of Escherichia coli. Mapping and cloning of its structural gene and identification of the enzyme as a periplasmic protein induced under high osmolarity growth conditions." J Biol Chem 1987;262(27);13212-8. PMID: 2820965
Giaever88: Giaever HM, Styrvold OB, Kaasen I, Strom AR (1988). "Biochemical and genetic characterization of osmoregulatory trehalose synthesis in Escherichia coli." J Bacteriol 1988;170(6);2841-9. PMID: 3131312
Gutierrez89: Gutierrez C, Ardourel M, Bremer E, Middendorf A, Boos W, Ehmann U (1989). "Analysis and DNA sequence of the osmoregulated treA gene encoding the periplasmic trehalase of Escherichia coli K12." Mol Gen Genet 1989;217(2-3);347-54. PMID: 2671658
Styrvold91: Styrvold OB, Strom AR (1991). "Synthesis, accumulation, and excretion of trehalose in osmotically stressed Escherichia coli K-12 strains: influence of amber suppressors and function of the periplasmic trehalase." J Bacteriol 173(3);1187-92. PMID: 1825082
Cardona09: Cardona F, Parmeggiani C, Faggi E, Bonaccini C, Gratteri P, Sim L, Gloster TM, Roberts S, Davies GJ, Rose DR, Goti A (2009). "Total syntheses of casuarine and its 6-O-alpha-glucoside: complementary inhibition towards glycoside hydrolases of the GH31 and GH37 families." Chemistry 15(7);1627-36. PMID: 19123216
Gibson07: Gibson RP, Gloster TM, Roberts S, Warren RA, Storch de Gracia I, Garcia A, Chiara JL, Davies GJ (2007). "Molecular basis for trehalase inhibition revealed by the structure of trehalase in complex with potent inhibitors." Angew Chem Int Ed Engl 46(22);4115-9. PMID: 17455176
HenggeAronis91: Hengge-Aronis R, Klein W, Lange R, Rimmele M, Boos W (1991). "Trehalose synthesis genes are controlled by the putative sigma factor encoded by rpoS and are involved in stationary-phase thermotolerance in Escherichia coli." J Bacteriol 173(24);7918-24. PMID: 1744047
Repoila91: Repoila F, Gutierrez C (1991). "Osmotic induction of the periplasmic trehalase in Escherichia coli K12: characterization of the treA gene promoter." Mol Microbiol 1991;5(3);747-55. PMID: 1710760
TourinhodosSant94: Tourinho-dos-Santos CF, Bachinski N, Paschoalin VM, Paiva CL, Silva JT, Panek AD (1994). "Periplasmic trehalase from Escherichia coli--characterization and immobilization on spherisorb." Braz J Med Biol Res 27(3);627-36. PMID: 8081287
Uhland00: Uhland K, Mondigler M, Spiess C, Prinz W, Ehrmann M (2000). "Determinants of translocation and folding of TreF, a trehalase of Escherichia coli." J Biol Chem 275(31);23439-45. PMID: 10816581
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