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MetaCyc Enzyme: trehalose synthase complex

Species: Saccharomyces cerevisiae

Subunit composition of trehalose synthase complex = [TPS3][TSL1][TPS2][TPS1]
         trehalose synthase complex regulatory subunit TPS3 = TPS3 (summary available)
         trehalose synthase complex regulatory subunit TSL1 = TSL1 (summary available)
         trehalose-6-phosphate phosphatase = TPS2 (summary available)
         trehalose-6-phosphate synthase = TPS1 (extended summary available)

Summary:
In Saccharomyces cerevisiae, α,α-trehalose and glycogen are major storage carbohydrates. α,α-trehalose is also involved in resistance to heat, dessication, and osmolarity changes. Changes in α,α-trehalose biosynthesis affect growth, glycogen accumulation and sporulation (in [De01]).

In early work on α,α-trehalose biosynthesis in Saccharomyces cerevisiae, trehalose-6-phosphate synthase was shown to transfer the D-glucose residue from UDP-α-D-glucose to α-D-glucose 6-phosphate, producing α,α-trehalose 6-phosphate and UDP. Dephosphorylation of α,α-trehalose 6-phosphate by trehalose-6-phosphate phosphatase produced α,α-trehalose [CABIB58]. Subsequent work identified a high molecular weight protein complex in Saccharomyces cerevisiae known as the trehalose synthase complex which contained both trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase activities [CABIB58, Londesborough91, Vandercammen89, Londesborough93].

Currently, characterization of the exact subunit composition and subunit stoichiometry in the trehalose synthase complex remains incomplete. The trehalose-6-phosphate synthase product of gene TPS1 (TSS1), the trehalose-6-phosphate phosphatase product of gene TPS2, and two regulatory protein products of genes TSL1 and TPS3 are known to be components of the 630-800 kDa trehalose synthase protein complex. The presence of all components is necessary for optimal activity [Londesborough91, Vandercammen89, Bell98], although both TPS1 and TPS2 are also functional as monomers. The reason for the existence of the complex, and its role in metabolism, remain incompletely defined [Chaudhuri08].

Gene-Reaction Schematic: ?

Credits:
Created 06-Feb-2012 by Fulcher CA , SRI International


Enzymatic reaction of: trehalose-6-phosphate phosphatase (trehalose synthase complex)

EC Number: 3.1.3.12

α,α-trehalose 6-phosphate + H2O <=> α,α-trehalose + phosphate

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.

The reaction is physiologically favored in the direction shown.

In Pathways: chitin biosynthesis , trehalose biosynthesis I


Enzymatic reaction of: trehalose-6-phosphate synthase (trehalose synthase complex)

EC Number: 2.4.1.15

UDP-α-D-glucose + α-D-glucose 6-phosphate <=> UDP + α,α-trehalose 6-phosphate + H+

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the Enzyme Commission system.

The reaction is favored in the direction shown.

In Pathways: chitin biosynthesis , trehalose biosynthesis I


Subunit of trehalose synthase complex: trehalose synthase complex regulatory subunit TPS3

Synonyms: α,α-trehalose-phosphate synthase [UDP-forming] 115 kDa subunit

Gene: TPS3 Accession Number: G-14926 (MetaCyc)

Molecular Weight: 118.84 kD (from nucleotide sequence)

Unification Links: DIP:DIP-891N , Mint:MINT-638595 , Protein Model Portal:P38426 , SMR:P38426 , String:4932.YMR261C , UniProt:P38426

Relationship Links: CAZy:IN-FAMILY:GT20 , InterPro:IN-FAMILY:IPR001830 , InterPro:IN-FAMILY:IPR003337 , InterPro:IN-FAMILY:IPR023214 , Pfam:IN-FAMILY:PF00982 , Pfam:IN-FAMILY:PF02358

Summary:
The TSL1 and TPS3 regulatory subunits of the trehalose synthase complex are homologs. Mutant studies suggested that they stabilize the trehalose synthase complex and that their functions are partially redundant [Bell98].


Subunit of trehalose synthase complex: trehalose synthase complex regulatory subunit TSL1

Synonyms: α,α-trehalose-phosphate synthase [UDP-forming] 123 kDa subunit

Gene: TSL1 Accession Number: G-14925 (MetaCyc)

Molecular Weight: 123.02 kD (from nucleotide sequence)

Unification Links: DIP:DIP-753N , Mint:MINT-640795 , Protein Model Portal:P38427 , SMR:P38427 , String:4932.YML100W , UniProt:P38427

Relationship Links: CAZy:IN-FAMILY:GT20 , InterPro:IN-FAMILY:IPR001830 , InterPro:IN-FAMILY:IPR003337 , InterPro:IN-FAMILY:IPR023214 , Pfam:IN-FAMILY:PF00982 , Pfam:IN-FAMILY:PF02358

Summary:
The TSL1 and TPS3 regulatory subunits of the trehalose synthase complex are homologs. Mutant studies suggested that they stabilize the trehalose synthase complex and that their functions are partially redundant [Bell98].


Component enzyme of trehalose synthase complex : trehalose-6-phosphate phosphatase

Synonyms: Tps2, trehalose synthase complex catalytic subunit TPS2

Gene: TPS2 Accession Number: G-451 (MetaCyc)

Molecular Weight: 102.98 kD (from nucleotide sequence)

Molecular Weight: 102.0 kD (experimental) [Londesborough93]

Unification Links: DIP:DIP-823N , Mint:MINT-396338 , ModBase:P31688 , Protein Model Portal:P31688 , SMR:P31688 , String:4932.YDR074W , Swiss-Model:P31688 , UniProt:P31688

Relationship Links: CAZy:IN-FAMILY:GT20 , InterPro:IN-FAMILY:IPR001830 , InterPro:IN-FAMILY:IPR003337 , InterPro:IN-FAMILY:IPR006379 , InterPro:IN-FAMILY:IPR023214 , Pfam:IN-FAMILY:PF00982 , Pfam:IN-FAMILY:PF02358

Catalyzes:
α,α-trehalose 6-phosphate + H2O → α,α-trehalose + phosphate

Summary:
The apparent molecular mass of the polypeptide was determined by SDS-PAGE [Londesborough93].

This enzyme participates in α,α-trehalose biosynthesis by dephosphorylating α,α-trehalose 6-phosphate to form α,α-trehalose. Disruption of the TPS2 gene was shown to result in a complete loss of trehalose-6-phosphate phosphatase activity and accumulation of α,α-trehalose 6-phosphate. The mutation had no effect on trehalose-6-phosphate synthase activity [De93].

TPS2 is part of the trehalose synthase protein complex (see trehalose synthase complex). Isolation of the TPS2 polypeptide from the complex showed that it can also function independently as a specific trehalose-6-phosphate phosphatase [Londesborough93].


Component enzyme of trehalose synthase complex : TPS1

Synonyms: Tps1, α,α-trehalose-phosphate synthase [UDP-forming] 56 kDa subunit, general glucose sensor subunit 1, glycogen metabolism control protein GLC6, trehalose synthase complex catalytic subunit TPS1

Gene: TPS1 Accession Number: G-454 (MetaCyc)

Molecular Weight: 56.148 kD (from nucleotide sequence)

Molecular Weight: 59.0 kD (experimental) [Chaudhuri08]

Unification Links: DIP:DIP-744N , Mint:MINT-618278 , ModBase:Q00764 , Pride:Q00764 , Protein Model Portal:Q00764 , SMR:Q00764 , String:4932.YBR126C , Swiss-Model:Q00764 , UniProt:Q00764

Relationship Links: CAZy:IN-FAMILY:GT20 , InterPro:IN-FAMILY:IPR001830 , InterPro:IN-FAMILY:IPR012766 , Pfam:IN-FAMILY:PF00982

Catalyzes:
UDP-α-D-glucose + α-D-glucose 6-phosphate → UDP + α,α-trehalose 6-phosphate + H+

Summary:
The apparent molecular mass of the polypeptide was determined by SDS-PAGE [Chaudhuri08].

TPS1 is part of the trehalose synthase protein complex (see trehalose synthase complex). Isolation of the TPS1 polypeptide from the complex showed that it can also function independently as a trehalose-6-phosphate synthase [Chaudhuri08, Chaudhuri09].

The native, uncomplexed TPS1 was purified and shown to be active as a trehalose-6-phosphate synthase, although it was unstable when separated from the complex. It appeared to be regulated by association and dissociation with other protein components [Chaudhuri08]. Its substrate specificity and factors for optimal activity have been determined [Chaudhuri09].

A purified, recombinant GST-TPS1 fusion protein expressed in Escherichia coli also showed high trehalose-6-phosphate synthase activity, and a H223Y mutant showed increased trehalose-6-phosphate synthase activity as compared with wild-type [De01].

TPS1 was shown to be required for α,α-trehalose synthesis and for growth on D-glucose and D-fructose. Mutant studies suggested that a portion of TPS1 may occur in uncomplexed form in vivo [Bell98]]|. TPS1 activity was inhibited by phosphate when TPS1 was in the trehalose synthase complex, but phosphate stimulated the monomeric form of TPS1 [Bell98].


References

Bell98: Bell W, Sun W, Hohmann S, Wera S, Reinders A, De Virgilio C, Wiemken A, Thevelein JM (1998). "Composition and functional analysis of the Saccharomyces cerevisiae trehalose synthase complex." J Biol Chem 273(50);33311-9. PMID: 9837904

CABIB58: CABIB E, LELOIR LF (1958). "The biosynthesis of trehalose phosphate." J Biol Chem 231(1);259-75. PMID: 13538966

Chaudhuri08: Chaudhuri P, Basu A, Ghosh AK (2008). "Aggregation dependent enhancement of trehalose-6-phosphate synthase activity in Saccharomyces cerevisiae." Biochim Biophys Acta 1780(2);289-97. PMID: 18166160

Chaudhuri09: Chaudhuri P, Basu A, Sengupta S, Lahiri S, Dutta T, Ghosh AK (2009). "Studies on substrate specificity and activity regulating factors of trehalose-6-phosphate synthase of Saccharomyces cerevisiae." Biochim Biophys Acta 1790(5);368-74. PMID: 19289151

De01: De Silva-Udawatta MN, Cannon JF (2001). "Roles of trehalose phosphate synthase in yeast glycogen metabolism and sporulation." Mol Microbiol 40(6);1345-56. PMID: 11442833

De93: De Virgilio C, Burckert N, Bell W, Jeno P, Boller T, Wiemken A (1993). "Disruption of TPS2, the gene encoding the 100-kDa subunit of the trehalose-6-phosphate synthase/phosphatase complex in Saccharomyces cerevisiae, causes accumulation of trehalose-6-phosphate and loss of trehalose-6-phosphate phosphatase activity." Eur J Biochem 212(2);315-23. PMID: 8444170

Londesborough91: Londesborough J, Vuorio O (1991). "Trehalose-6-phosphate synthase/phosphatase complex from bakers' yeast: purification of a proteolytically activated form." J Gen Microbiol 1991;137 ( Pt 2);323-30. PMID: 1849964

Londesborough93: Londesborough J, Vuorio OE (1993). "Purification of trehalose synthase from baker's yeast. Its temperature-dependent activation by fructose 6-phosphate and inhibition by phosphate." Eur J Biochem 1993;216(3);841-8. PMID: 8404904

Vandercammen89: Vandercammen A, Francois J, Hers HG (1989). "Characterization of trehalose-6-phosphate synthase and trehalose-6-phosphate phosphatase of Saccharomyces cerevisiae." Eur J Biochem 182(3);613-20. PMID: 2546763


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 SRI International Pathway Tools version 18.5 on Mon Dec 22, 2014, biocyc12.