title: Enzymatic and regulatory properties of the trehalose-6-phosphate synthase from the thermoacidophilic archaeon Thermoplasma acidophilum.
abstract: Trehalose-6-phosphate synthase plays an important role in trehalose metabolism. It catalyzes the transfer of glucose from UDP-glucose (UDPG) to glucose 6-phosphate to produce trehalose-6-phosphate. Herein we describe the characterization of a trehalose-6-phosphate synthase from the thermoacidophilic archaeon Thermoplasma acidophilum. The dimeric enzyme could utilize UDPG, ADP-Glucose (ADPG) and GDP-Glucose (GDPG) as glycosyl donors and various phosphorylated monosaccharides as glycosyl acceptors. The optimal temperature and pH were found to be 60 °C and pH 6, and the enzyme exhibited notable pH and thermal stability. The enzymatic activity could be stimulated by divalent metal ions and polyanions heparin and chondroitin sulfate. Moreover, the protein was considerably resistant to additives ethanol, EDTA, urea, DTT, SDS, β-mercaptoethanol, methanol, isopropanol and n-butanol. Molecular modeling and mutagenesis analysis revealed that the N-loop region was important for the catalytic efficiency of the enzyme, indicating different roles of N-loop sequences in different trehalose-6-phosphate synthases.
authors: College of Food and Bioengineering, Qilu University of Technology, Jinan, Shandong 250353, PR China.
authors: Yanyan
authors: Y
authors: Gao
authors: College of Food and Bioengineering, Qilu University of Technology, Jinan, Shandong 250353, PR China.
authors: Ying
authors: Y
authors: Jiang
authors: College of Food and Bioengineering, Qilu University of Technology, Jinan, Shandong 250353, PR China.
authors: Qiulei
authors: Q
authors: Liu
authors: College of Food and Bioengineering, Qilu University of Technology, Jinan, Shandong 250353, PR China.
authors: Ruiming
authors: R
authors: Wang
authors: College of Food and Bioengineering, Qilu University of Technology, Jinan, Shandong 250353, PR China.
authors: Xinli
authors: X
authors: Liu
authors: College of Food and Bioengineering, Qilu University of Technology, Jinan, Shandong 250353, PR China. Electronic address: ertrdfgg@aliyun.com.
authors: Bo
authors: B
authors: Liu
mesh_terms: D000245:Adenosine Diphosphate Glucose / Q000737:chemistry; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D019843:Archaeal Proteins / Q000737:chemistry* / Q000235:genetics; D020134:Catalytic Domain; D004795:Enzyme Stability; D005964:Glucosyltransferases / Q000737:chemistry* / Q000235:genetics; D006031:Glycosylation; D006156:Guanosine Diphosphate Sugars / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008274:Magnesium / Q000737:chemistry; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011489:Protein Denaturation; D020836:Protein Structure, Quaternary; D013379:Substrate Specificity; D013822:Thermoplasma / Q000201:enzymology*; D014532:Uridine Diphosphate Glucose / Q000737:chemistry; D015032:Zinc / Q000737:chemistry
chemical_list: D019843:Archaeal Proteins; D006156:Guanosine Diphosphate Sugars; D000245:Adenosine Diphosphate Glucose; C100085:guanosine diphosphate glucose; D005964:Glucosyltransferases; C023180:trehalose-6-phosphate synthase; D008274:Magnesium; D015032:Zinc; D014532:Uridine Diphosphate Glucose
keywords: Enzyme regulation; Molecular modeling; N-Loop sequence; Thermoplasma acidophilum; Trehalose-6-phosphate synthase; pH and thermal stability