alpha,alpha-trehalose-phosphate synthase [UDP-forming]. This enzyme catalyzes the key, penultimate step in biosynthesis of trehalose, a compatible solute made as an osmoprotectant in some species in all three domains of life. The gene symbol OtsA stands for osmotically regulated trehalose synthesis A. Trehalose helps protect against both osmotic and thermal stresses, and is made from two glucose subunits. This model excludes glucosylglycerol-phosphate synthase, an enzyme of an analogous osmoprotectant system in many cyanobacterial strains. This model does not identify archaeal examples, as they are more divergent than glucosylglycerol-phosphate synthase. Sequences that score in the gray zone between the trusted and noise cutoffs include a number of yeast multidomain proteins in which the N-terminal domain may be functionally equivalent to this family. The gray zone also includes the OtsA of Cornyebacterium glutamicum (and related species), shown to be responsible for synthesis of only trace amounts of trehalose while the majority is synthesized by the TreYZ pathway; the significance of OtsA in this species is unclear (see Wolf, et al., ). [Cellular processes, Adaptations to atypical conditions]

trehalose-6-phosphate synthase. Trehalose-6-Phosphate Synthase (TPS, EC 2.4.1.15) is a glycosyltransferase that catalyses the synthesis of alpha,alpha-1,1-trehalose-6-phosphate from glucose-6-phosphate using a UDP-glucose donor. It is a key enzyme in the trehalose synthesis pathway. Trehalose is a nonreducing disaccharide present in a wide variety of organisms and may serve as a source of energy and carbon. It is characterized most notably in insect, plant, and microbial cells. Its production is often associated with a variety of stress conditions, including desiccation, dehydration, heat, cold, and oxidation. This family represents the catalytic domain of the TPS. Some members of this domain family coexist with a C-terminal trehalose phosphatase domain.

Trehalose-6-phosphate synthase [Carbohydrate transport and metabolism].

Glycosyltransferase family 20. Members of this family belong to glycosyl transferase family 20. OtsA (Trehalose-6-phosphate synthase) is homologous to regions in the subunits of yeast trehalose-6-phosphate synthase/phosphate complex,.

putative bifunctional trehalose-6-phosphate synthase/HAD hydrolase subfamily IIB; Provisional

Crystalstructure of an UDP-forming alpha, alpha-terhalose-phosphate synthase from Burkholderia xenovorans [Paraburkholderia xenovorans LB400]

OtsAapo structure [Escherichia coli],6JAK_B OtsA apo structure [Escherichia coli],6JAK_C OtsA apo structure [Escherichia coli],6JAK_D OtsA apo structure [Escherichia coli]

Insightinto the mechanism of enzymatic glycosyltransfer with retention through the synthesis and analysis of bisubstrate glycomimetics of trehalose-6-phosphate synthase [Escherichia coli K-12],2WTX_B Insight into the mechanism of enzymatic glycosyltransfer with retention through the synthesis and analysis of bisubstrate glycomimetics of trehalose-6-phosphate synthase [Escherichia coli K-12],2WTX_C Insight into the mechanism of enzymatic glycosyltransfer with retention through the synthesis and analysis of bisubstrate glycomimetics of trehalose-6-phosphate synthase [Escherichia coli K-12],2WTX_D Insight into the mechanism of enzymatic glycosyltransfer with retention through the synthesis and analysis of bisubstrate glycomimetics of trehalose-6-phosphate synthase [Escherichia coli K-12]

Trehalose-6-phosphatefrom E. coli bound with UDP-2-fluoro glucose. [Escherichia coli],1UQT_B Trehalose-6-phosphate from E. coli bound with UDP-2-fluoro glucose. [Escherichia coli],1UQU_A Trehalose-6-phosphate from E. coli bound with UDP-glucose. [Escherichia coli],1UQU_B Trehalose-6-phosphate from E. coli bound with UDP-glucose. [Escherichia coli]

Trehalose-6-phosphatesynthase. OtsA [Escherichia coli],1GZ5_B Trehalose-6-phosphate synthase. OtsA [Escherichia coli],1GZ5_C Trehalose-6-phosphate synthase. OtsA [Escherichia coli],1GZ5_D Trehalose-6-phosphate synthase. OtsA [Escherichia coli]

Trehalose-6-phosphate synthase OS=Klebsiella pneumoniae subsp. pneumoniae (strain ATCC 700721 / MGH 78578) OX=272620 GN=otsA PE=3 SV=1

Trehalose-6-phosphate synthase OS=Citrobacter koseri (strain ATCC BAA-895 / CDC 4225-83 / SGSC4696) OX=290338 GN=otsA PE=3 SV=2

Trehalose-6-phosphate synthase OS=Enterobacter sp. (strain 638) OX=399742 GN=otsA PE=3 SV=1

Trehalose-6-phosphate synthase OS=Escherichia coli O9:H4 (strain HS) OX=331112 GN=otsA PE=3 SV=1

Trehalose-6-phosphate synthase OS=Escherichia coli (strain SMS-3-5 / SECEC) OX=439855 GN=otsA PE=3 SV=1